Unable to install microG services [INSTALL_FAILED_CONFLICTING_PROVIDER]

Describe the bug
Unable to install microG services (com.google.android.gms) via ADB or the default installer

To Reproduce
Steps to reproduce the behavior:
(on pc)
Running adb install <path_to_microg_Services.apk> fails with:
Failure [INSTALL_FAILED_CONFLICTING_PROVIDER]
On android it fails simply with "App not installed"

Expected behavior
microG would install

Screenshots

CMD output below

System
Android Version: Android 4.4.4
Custom ROM: Stock samsung os (touchwiz)

Additional context
Signature Spoofing is enabled (checked with Signature Spoof Checker)
ROM is rooted and deoxed
there is zero traces of com.google.android.gms
here is the cmd shell output:

Microsoft Windows [Version 10.0.26200.7623]
(c) Microsoft Corporation. All rights reserved.

C:\Users\Riccar10210\Desktop\microg>adb install "com.google.android.gms-250932022(2).apk"
Performing Push Install
com.google.android.gms-250932022(2).apk: 1 file pushed, 0 skipped. 4.7 MB/s (105504117 bytes in 21.503s)
        pkg: /data/local/tmp/com.google.android.gms-250932022(2).apk
Failure [INSTALL_FAILED_CONFLICTING_PROVIDER]

C:\Users\Riccar10210\Desktop\microg>adb push "com.google.android.gms-250932022(2).apk" /sdcard
com.google.android.gms-250932022(2).apk: 1 file pushed, 0 skipped. 4.8 MB/s (105504117 bytes in 21.113s)

C:\Users\Riccar10210\Desktop\microg>adb uninstall com.google.android.gmns
^C
C:\Users\Riccar10210\Desktop\microg>adb uninstall com.google.android.gms
Failure

C:\Users\Riccar10210\Desktop\microg>adb shell
root@heatqlte:/ # su
root@heatqlte:/ # ls /system/priv-app
AutoPreconfig.apk
AutomationTest_FB.apk
BackupRestoreConfirmation.apk
CSC.apk
ConfigUpdater.apk
DSMLawmo.apk
DefaultContainerService.apk
DeviceKeystring.apk
DeviceTest.apk
DiagMonAgent.apk
ExternalStorageProvider.apk
FmmDM.apk
FmmDS.apk
FotaClient.apk
FusedLocation.apk
GalaxyApps_hdpi.apk
GmsCore
HwModuleTest.apk
HybridRadio_ESS.apk
InputDevices.apk
KLMSAgent.apk
Keyguard_ESS.apk
Kies.apk
LogsProvider.apk
MtpApplication.apk
MusicFX.apk
OmaCP.apk
PCWClientS18.apk
PageBuddyNotiSvc2.apk
PhoneErrService.apk
ProxyHandler.apk
SPDClient.apk
SPPPushClient_Prod.apk
SamsungBilling.apk
Samsungservice2_hdpi.apk
SecCalendarProvider_NOTSTICKER.apk
SecContactsProvider.apk
SecContacts_ENTRY.apk
SecDownloadProvider.apk
SecGallery_ESS.apk
SecLauncher3_ESS.apk
SecLiveWallpapersPicker_ESS.apk
SecMediaProvider.apk
SecMms_ESS.apk
SecMyFiles2014_ESS.apk
SecSettingsProvider.apk
SecSettings_ESS.apk
SecSetupWizard_ESS.apk
SecVideoPlayer_ESS2.apk
SecVideo_ESS.apk
SecWallpaperChooser_ESS.apk
ServiceModeApp_RIL.apk
SetupWizard.apk
SharedStorageBackup.apk
Shell.apk
SyncmlDM.apk
SystemUI_ESS.apk
Tag.apk
TeleService_ESS.apk
VpnDialogs.apk
WallpaperCropper.apk
com.qualcomm.location.apk
serviceModeApp_FB.apk
wssyncmlnps.apk
root@heatqlte:/ #

getprop status:

C:\Users\Riccar10210\Desktop\microg>adb shell getprop
[DEVICE_PROVISIONED]: [1]
[af.resampler.quality]: [4]
[audio.offload.buffer.size.kb]: [32]
[audio.offload.gapless.enabled]: [true]
[av.offload.enable]: [true]
[bluetooth.hciattach]: [true]
[bluetooth.status]: [on]
[dalvik.vm.heapgrowthlimit]: [128m]
[dalvik.vm.heapmaxfree]: [4m]
[dalvik.vm.heapminfree]: [1m]
[dalvik.vm.heapsize]: [256m]
[dalvik.vm.heapstartsize]: [8m]
[dalvik.vm.heaptargetutilization]: [0.75]
[dalvik.vm.stack-trace-file]: [/data/anr/traces.txt]
[debug.composition.type]: [c2d]
[debug.egl.hw]: [1]
[debug.force_rtl]: [0]
[debug.mdpcomp.logs]: [0]
[debug.sf.hw]: [1]
[debug.sf.layerdump]: [0]
[dev.MDPLimitCondition]: [0]
[dev.bootcomplete]: [1]
[dev.kies.sommode]: [TRUE]
[dev.kiessupport]: [TRUE]
[dev.knoxapp.running]: [false]
[dev.pm.dyn_samplingrate]: [1]
[dev.ssrm.emergencymode]: [false]
[dev.ssrm.init]: [1]
[dev.ssrm.mode]: []
[dhcp.wlan0.leasetime]: [21600]
[dhcp.wlan0.mask]: [255.255.255.0]
[dhcp.wlan0.mtu]: []
[dhcp.wlan0.pid]: [20886]
[dhcp.wlan0.reason]: [REBOOT]
[dhcp.wlan0.result]: [ok]
[dhcp.wlan0.roaming]: [0]
[dhcp.wlan0.server]: [192.168.1.1]
[dhcp.wlan0.vendorInfo]: []
[gsm.current.phone-type]: [1]
[gsm.network.type]: [Unknown:0]
[gsm.operator.alpha]: []
[gsm.operator.iso-country]: [it]
[gsm.operator.ispsroaming]: [false]
[gsm.operator.isroaming]: [false]
[gsm.operator.numeric]: [22299]
[gsm.sim.state]: [ABSENT]
[gsm.version.baseband]: [G357FZXXU1AOE1]
[gsm.version.ril-impl]: [Samsung RIL v3.0]
[init.svc.BCS-daemon]: [running]
[init.svc.DR-daemon]: [running]
[init.svc.SMD-daemon]: [running]
[init.svc.Sh2YFhXXzmXcYOP]: [stopped]
[init.svc.WjHE0pPZd]: [stopped]
[init.svc.adbd]: [running]
[init.svc.at_distributor]: [running]
[init.svc.atfwd]: [stopped]
[init.svc.auditd]: [running]
[init.svc.bootanim]: [stopped]
[init.svc.cnd]: [running]
[init.svc.config_bluetooth]: [stopped]
[init.svc.cs_service]: [running]
[init.svc.debuggerd]: [running]
[init.svc.dhcpcd_wlan0]: [running]
[init.svc.diag_uart_log]: [running]
[init.svc.dpmd]: [restarting]
[init.svc.drm]: [running]
[init.svc.drsd]: [running]
[init.svc.hciattach]: [stopped]
[init.svc.healthd]: [running]
[init.svc.i4ZcspJqog7b]: [stopped]
[init.svc.icd]: [stopped]
[init.svc.imsdatadaemon]: [restarting]
[init.svc.imsqmidaemon]: [running]
[init.svc.installd]: [running]
[init.svc.iprenew_wlan0]: [stopped]
[init.svc.irsc_util]: [stopped]
[init.svc.keystore]: [running]
[init.svc.knox]: [stopped]
[init.svc.macloader]: [stopped]
[init.svc.media]: [running]
[init.svc.mobex-daemon]: [running]
[init.svc.mpdecision]: [running]
[init.svc.netd]: [running]
[init.svc.netmgrd]: [stopped]
[init.svc.p2p_supplicant]: [running]
[init.svc.powersnd]: [stopped]
[init.svc.prepare_param]: [stopped]
[init.svc.qcamerasvr]: [running]
[init.svc.qcom-c_core-sh]: [stopped]
[init.svc.qcom-post-boot]: [stopped]
[init.svc.qcom-sh]: [stopped]
[init.svc.qcom-usb-sh]: [stopped]
[init.svc.qmuxd]: [running]
[init.svc.qrngd]: [running]
[init.svc.qrngp]: [stopped]
[init.svc.qseecomd]: [running]
[init.svc.rfs_access]: [running]
[init.svc.ril-daemon]: [running]
[init.svc.rmt_storage]: [running]
[init.svc.rtccd]: [stopped]
[init.svc.sdcard]: [stopped]
[init.svc.sdumpstate]: [stopped]
[init.svc.servicemanager]: [running]
[init.svc.surfaceflinger]: [running]
[init.svc.thermal-engine]: [running]
[init.svc.time_daemon]: [running]
[init.svc.ueventd]: [running]
[init.svc.vold]: [running]
[init.svc.wcnss-service]: [running]
[init.svc.zygote]: [running]
[installd.sdcard_manipulate_done]: [1]
[keyguard.no_require_sim]: [true]
[media.aac_51_output_enabled]: [true]
[media.stagefright.enable-aac]: [true]
[media.stagefright.enable-fma2dp]: [true]
[media.stagefright.enable-http]: [true]
[media.stagefright.enable-player]: [true]
[media.stagefright.enable-qcp]: [true]
[media.stagefright.enable-scan]: [true]
[mm.enable.qcom_parser]: [262143]
[mmp.enable.3g2]: [true]
[net.bt.name]: [Android]
[net.change]: [net.dns1]
[net.dns1]: [192.168.1.1]
[net.hostname]: [android-cb188fd508908d89]
[net.knoxisl.version]: [2.0.0]
[net.knoxscep.version]: [2.0.0]
[net.knoxsso.version]: [2.1.1]
[net.knoxvpn.version]: [2.2.0]
[net.mt.init]: [DONE]
[net.qtaguid_enabled]: [1]
[net.tcp.buffersize.default]: [4096,87380,704512,4096,16384,110208]
[net.tcp.buffersize.edge]: [4093,26280,35040,4096,16384,35040]
[net.tcp.buffersize.evdo]: [4094,87380,262144,4096,16384,262144]
[net.tcp.buffersize.gprs]: [4092,30000,30000,4096,8760,11680]
[net.tcp.buffersize.hsdpa]: [4094,87380,704512,4096,16384,262144]
[net.tcp.buffersize.hspa]: [4094,87380,704512,4096,16384,262144]
[net.tcp.buffersize.hspap]: [4094,87380,1220608,4096,16384,1220608]
[net.tcp.buffersize.hsupa]: [4094,87380,704512,4096,16384,262144]
[net.tcp.buffersize.lte]: [524288,1048576,2560000,524288,1048576,2560000]
[net.tcp.buffersize.umts]: [4094,87380,704512,4096,16384,110208]
[net.tcp.buffersize.wifi]: [524288,1048576,4525824,524288,1048576,4525824]
[net.tcp.default_init_rwnd]: [60]
[persist.audio.allsoundmute]: [0]
[persist.audio.fluence.speaker]: [true]
[persist.audio.fluence.voicecall]: [true]
[persist.audio.fluence.voicerec]: [false]
[persist.audio.headsetsysvolume]: [9]
[persist.audio.hphonesysvolume]: [9]
[persist.audio.ringermode]: [0]
[persist.audio.sysvolume]: [9]
[persist.cne.feature]: [0]
[persist.data.netmgrd.qos.enable]: [false]
[persist.demo.hdmirotationlock]: [false]
[persist.fuse_sdcard]: [true]
[persist.gps.qc_nlp_in_use]: [1]
[persist.hwc.mdpcomp.enable]: [true]
[persist.loc.nlp_name]: [com.qualcomm.services.location]
[persist.radio.add_power_save]: [1]
[persist.radio.apm_sim_not_pwdn]: [1]
[persist.radio.atfwd.start]: [false]
[persist.radio.initphone-type]: [1]
[persist.radio.plmnname_1]: []
[persist.radio.plmnname_2]: []
[persist.rild.nitz_long_ons_0]: []
[persist.rild.nitz_long_ons_1]: []
[persist.rild.nitz_long_ons_2]: []
[persist.rild.nitz_long_ons_3]: []
[persist.rild.nitz_plmn]: []
[persist.rild.nitz_short_ons_0]: []
[persist.rild.nitz_short_ons_1]: []
[persist.rild.nitz_short_ons_2]: []
[persist.rild.nitz_short_ons_3]: []
[persist.security.ams.enforcing]: [1]
[persist.sys.clssprld1]: [604]
[persist.sys.clssprld2]: [802]
[persist.sys.country]: [US]
[persist.sys.dalvik.vm.lib]: [libdvm.so]
[persist.sys.drs.date]: [Tue May 12 12:53:02 KST 2015]
[persist.sys.flipfontpath]: [default]
[persist.sys.language]: [en]
[persist.sys.localevar]: []
[persist.sys.profiler_ms]: [0]
[persist.sys.setupwizard]: [FINISH]
[persist.sys.silent]: [1]
[persist.sys.storage_preload]: [2]
[persist.sys.strict_op_enable]: [false]
[persist.sys.timezone]: [Europe/Rome]
[persist.sys.usb.config.extra]: [none]
[persist.sys.usb.config]: [mtp,adb]
[persist.timed.enable]: [true]
[ril.CompleteMsg]: [01]
[ril.ICC_TYPE]: [0]
[ril.RildInit]: [1]
[ril.atd_status]: [1_1_0]
[ril.cs_svc]: [1]
[ril.deviceOffRes]: [0]
[ril.ecclist0]: [112,911,999,000,08,110,118,119]
[ril.ecclist]: [911,*911,#911,112,000,08,110,999,118,119]
[ril.hw_ver]: [MP 0.400]
[ril.ims.ecsupport]: [2]
[ril.ims.ltevoicesupport]: [2]
[ril.modem.board]: [MSM8916]
[ril.product_code]: [SM-G357FZAZITV]
[ril.radiostate]: [10]
[ril.rfcal_date]: [2015.06.08]
[ril.sales_code]: [ITV]
[ril.serialnumber]: [00000000000]
[ril.servicestate]: [2]
[ril.subscription.types]: [NV,RUIM]
[ril.sw_ver]: [G357FZXXU1AOE1]
[ril.timezoneID]: [Europe/Rome]
[rild.libargs]: [-d /dev/smd0]
[rild.libpath]: [/system/lib/libsec-ril.so]
[ro.adb.secure]: [1]
[ro.alarm_boot]: [false]
[ro.allow.mock.location]: [0]
[ro.baseband]: [msm]
[ro.bluetooth.dun]: [true]
[ro.bluetooth.hfp.ver]: [1.6]
[ro.bluetooth.sap]: [true]
[ro.board.platform]: [msm8916]
[ro.boot.baseband]: [msm]
[ro.boot.bootdevice]: [7824900.sdhci]
[ro.boot.bootloader]: [G357FZXXU1AOE1]
[ro.boot.cp_debug_level]: [0x55FF]
[ro.boot.debug_level]: [0x4f4c]
[ro.boot.emmc]: [true]
[ro.boot.hardware]: [qcom]
[ro.boot.sec_atd.tty]: [/dev/ttyHSL0]
[ro.boot.warranty_bit]: [0]
[ro.boot_recovery]: [unknown]
[ro.bootloader]: [G357FZXXU1AOE1]
[ro.bootmode]: [unknown]
[ro.bt.bdaddr_path]: [/efs/bluetooth/bt_addr]
[ro.build.PDA]: [G357FZXXU1AOE1]
[ro.build.changelist]: [572060]
[ro.build.characteristics]: [default]
[ro.build.date.utc]: [1431402782]
[ro.build.date]: [Tue May 12 12:53:02 KST 2015]
[ro.build.description]: [heatqltexx-user 4.4.4 KTU84P G357FZXXU1AOE1 release-keys]
[ro.build.display.id]: [KTU84P.G357FZXXU1AOE1]
[ro.build.fingerprint]: [samsung/heatqltexx/heatqlte:4.4.4/KTU84P/G357FZXXU1AOE1:user/release-keys]
[ro.build.hidden_ver]: [G357FZXXU1AOE1]
[ro.build.host]: [SWDD6204]
[ro.build.id]: [KTU84P]
[ro.build.knox.container]: []
[ro.build.product]: [heatqlte]
[ro.build.scafe.shot]: [single]
[ro.build.scafe.size]: [short]
[ro.build.scafe]: [macchiato]
[ro.build.selinux.enforce]: [1]
[ro.build.selinux]: [1]
[ro.build.tags]: [release-keys]
[ro.build.type]: [user]
[ro.build.user]: [dpi]
[ro.build.version.codename]: [REL]
[ro.build.version.incremental]: [G357FZXXU1AOE1]
[ro.build.version.release]: [4.4.4]
[ro.build.version.sdk]: [19]
[ro.carrier]: [unknown]
[ro.chipname]: [MSM8916]
[ro.com.android.dateformat]: [MM-dd-yyyy]
[ro.com.google.clientidbase]: [android-samsung]
[ro.com.google.gmsversion]: [4.4_r6]
[ro.config.alarm_alert]: [Morning_flower.ogg]
[ro.config.knox]: [v30]
[ro.config.max_starting_bg]: [8]
[ro.config.media_sound]: [Media_preview_Touch_the_light.ogg]
[ro.config.notification_sound]: [S_Whistle.ogg]
[ro.config.ringtone]: [Over_the_horizon.ogg]
[ro.config.tima]: [1]
[ro.config.timaversion]: [3.0]
[ro.cp_debug_level]: [0x55FF]
[ro.crypto.state]: [unencrypted]
[ro.data.large_tcp_window_size]: [true]
[ro.debug_level]: [0x4f4c]
[ro.debuggable]: [0]
[ro.emmc]: [true]
[ro.emmc_checksum]: [unknown]
[ro.error.receiver.default]: [com.samsung.receiver.error]
[ro.factorytest]: [0]
[ro.fm.transmitter]: [false]
[ro.gps.agps_provider]: [1]
[ro.hardware]: [qcom]
[ro.kernel.qemu]: [0]
[ro.nvdata_backup]: [unknown]
[ro.opengles.version]: [196608]
[ro.pip.gated]: [0]
[ro.product.board]: [MSM8916]
[ro.product.brand]: [samsung]
[ro.product.cpu.abi2]: [armeabi]
[ro.product.cpu.abi]: [armeabi-v7a]
[ro.product.device]: [heatqlte]
[ro.product.locale.language]: [en]
[ro.product.locale.region]: [GB]
[ro.product.manufacturer]: [samsung]
[ro.product.model]: [SM-G357FZ]
[ro.product.name]: [heatqltexx]
[ro.product_ship]: [true]
[ro.qc.sdk.audio.fluencetype]: [none]
[ro.qc.sdk.audio.ssr]: [false]
[ro.qualcomm.bluetooth.ftp]: [true]
[ro.qualcomm.bluetooth.hfp]: [true]
[ro.qualcomm.bluetooth.hsp]: [true]
[ro.qualcomm.bluetooth.map]: [true]
[ro.qualcomm.bluetooth.nap]: [true]
[ro.qualcomm.bluetooth.opp]: [true]
[ro.qualcomm.bluetooth.pbap]: [true]
[ro.qualcomm.bt.hci_transport]: [smd]
[ro.qualcomm.cabl]: [0]
[ro.revision]: [2]
[ro.ril.svdo]: [false]
[ro.ril.svlte1x]: [false]
[ro.runtime.firstboot]: [1769213923291]
[ro.sec.fle.encryption]: [true]
[ro.secure]: [1]
[ro.security.icd.flagmode]: [single]
[ro.setupwizard.mode]: [OPTIONAL]
[ro.sf.lcd_density]: [240]
[ro.telephony.call_ring.multiple]: [false]
[ro.use_data_netmgrd]: [false]
[ro.vendor.extension_library]: [/vendor/lib/libqc-opt.so]
[ro.warranty_bit]: [0]
[ro.wifi.channels]: []
[rw.km_fips_status]: [ready]
[sec.fle.encryption.status]: [Dec NewFile IncludeMedia]
[secmm.player.disabledivx]: [True]
[selinux.reload_policy]: [1]
[service.bootanim.exit]: [1]
[service.bt.security.policy.mode]: [2]
[service.media.powersnd]: [1]
[storage.mmc.size]: [7818182656]
[storage.preload.complete]: [1]
[sys.boot_completed]: [1]
[sys.cameramode.blackbox]: [0]
[sys.cameramode.vtcall]: [0]
[sys.dumpstate.opt]: [-k -t -z -d -m 2745 -o /data/log/dumpstate_app_error]
[sys.enterprise.billing.version]: [1.0.0]
[sys.factory.mediaScanningCount]: [24]
[sys.ims.QMI_DAEMON_STATUS]: [1]
[sys.knox.exists]: [0]
[sys.knox.store]: [0]
[sys.qseecomd.enable]: [true]
[sys.settings_global_version]: [2]
[sys.settings_system_version]: [87]
[sys.siop.level]: [0]
[sys.ssrm.mdnie]: [-1]
[sys.sysctl.extra_free_kbytes]: [4500]
[sys.sysctl.tcp_def_init_rwnd]: [60]
[sys.usb.config]: [mtp,adb]
[sys.usb.state]: [mtp,adb]
[telephony.lteOnCdmaDevice]: [0]
[tunnel.audio.encode]: [false]
[use.voice.path.for.pcm.voip]: [true]
[vold.post_fs_data_done]: [1]
[wifi.interface]: [wlan0]
[wlan.driver.ath]: [0]
[wlan.driver.status]: [ok]

C:\Users\Riccar10210\Desktop\microg>

Start by reproducing the reported adb install failure on Android 4.4.4 using the supplied com.google.android.gms APK and inspect the existing GmsCore installation under /system/priv-app. Confirm what provider conflict remains and document or implement a verified resolution, with success defined as installing microG without INSTALL_FAILED_CONFLICTING_PROVIDER.