[Bug]: Unable to connect to 7 days to die server

### User story

As a game server admin, i want to setup a 7 days to die server so that my users can play together.

### Game

7 days to die

### Linux distro

Ubuntu 24.04

### Command

command: start

### Further information

I am attempting to run 7 days to die on my server, but clients on the LAN are unable to connect (I haven't tried internet clients yet). What's weird is that I can successfully connect to the telnet and web server for the game from clients on the LAN, and the first time that a game client tries to connect I can see UDP packets flowing on the game port - but ultimately the client fails with "unable to retrieve server information". I do not have a firewall on the server whatsoever - and I've had 7days to die running on this server (same ports) successfully in the past with an older docker image. I also have many other game servers running successfully. The server is a 32 core AMD EPYC 7502P with 128GB of RAM. The server has plenty of resources, it's just a server for my home that runs various daemons and game servers for my kids and their friends.

Here's the docker compose:
```yml

7dtdserver:
image: gameservermanagers/gameserver:sdtd
environment:
- UID=${SEVEN_DAYS_TO_DIE_UID}
- GID=${SEVEN_DAYS_TO_DIE_GID}
- STEAM_USERID=${SEVEN_DAYS_TO_DIE_UID}
- STEAM_GROUPID=${SEVEN_DAYS_TO_DIE_GID}
- USERID=${SEVEN_DAYS_TO_DIE_UID}
- GROUPID=${SEVEN_DAYS_TO_DIE_GID}
- SERVER_IP=0.0.0.0
- SERVER_PORT=26900
- GAME_PORT=26900
- QUERY_PORT=26900
volumes:
- /storage/docker/7dtdserver:/data # 7 Days To Die world saves
ports:
- ${SEVEN_DAYS_TO_DIE_IP}:26900:26900/tcp # Default game ports
- ${SEVEN_DAYS_TO_DIE_IP}:26900:26900/udp # Default game ports
- ${SEVEN_DAYS_TO_DIE_IP}:26901:26901/udp # Default game ports
- ${SEVEN_DAYS_TO_DIE_IP}:26902:26902/udp # Default game ports
- ${SEVEN_DAYS_TO_DIE_IP}:8080:8080/tcp # OPTIONAL - WEBADMIN
- ${SEVEN_DAYS_TO_DIE_IP}:8081:8081/tcp # OPTIONAL - TELNET
- ${SEVEN_DAYS_TO_DIE_IP}:8082:8082/tcp # OPTIONAL - WEBSERVER https://7dtd.illy.bz/wiki/Server%20fixes
restart: unless-stopped # INFO - NEVER USE WITH START_MODE=4 or START_MODE=0
```

Here's my network config:
```yml
network:
version: 2
renderer: networkd
ethernets:
enp65s0f1:
dhcp4: false
dhcp6: false
addresses:
- 192.168.86.20/24
- 192.168.86.21/24
- 192.168.86.22/24
- 192.168.86.23/24
- 192.168.86.24/24
- 192.168.86.25/24
- 192.168.86.26/24
- 192.168.86.27/24
- 192.168.86.28/24
- 192.168.86.29/24
- 192.168.86.30/24
- 192.168.86.31/24
- 192.168.86.32/24
- 192.168.86.33/24
- 192.168.86.34/24
- 192.168.86.35/24
- 192.168.86.36/24
- 192.168.86.37/24
- 192.168.86.38/24
routes:
- to: default
via: 192.168.86.1
nameservers:
addresses: [192.168.86.1]
optional: true
```

And the server config xml:
```xml

```

And my sdtdserver.cfg:
```
##################################
####### Instance Settings ########
##################################
# PLACE INSTANCE SETTINGS HERE
## These settings will apply to a specific instance.

ip="0.0.0.0"
querymode="2"
querytype="sdtd"
queryport="26900"
```

### Relevant log output

```shell
for Update sdtdserver
=================================
[ .... ] Updating sdtdserver:
Installing Gamedig
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 746 100 746 0 0 13005 0 --:--:-- --:--:-- --:--:-- 13087
npm warn deprecated event-to-promise@0.7.0: Use promise-toolbox/fromEvent instead
npm warn deprecated mvdan-sh@0.10.1: See https://github.com/mvdan/sh/issues/1145

added 60 packages, and audited 61 packages in 1s

18 packages are looking for funding
run `npm fund` for details

found 0 vulnerabilities
[ OK ] Updating sdtdserver: Checking for update: SteamCMD

No update available
* Local build: 19449443
* Remote build: 19449443
* Branch: public
https://steamdb.info/app/294420/history

Starting sdtdserver
=================================
[ OK ] Starting sdtdserver: 7 days to Die

Distro Details
================================================================================
Date: Sun Aug 31 01:35:23 AM UTC 2025
Distro: Ubuntu 24.04.2 LTS
Arch: x86_64
Kernel: 5.15.0-139-generic
Hostname: ef6d2aea488a
Environment: docker
Uptime: 120d, 20h, 2m
tmux: 3.4
glibc: 2.39

Server Resource
================================================================================
CPU
Model: AMD EPYC 7502P 32-Core Processor
Cores: 64
Frequency: 2200.000MHz
Avg Load: 4.12, 2.74, 2.47

Memory
Mem: total used free cached available
Physical: 126GB 14GB 112GB 106GB 112GB
Swap: 0B 0B 0B

Storage
Filesystem: overlay
Total: 953G
Used: 317G
Available: 636G

Network
IP: 0.0.0.0
Internet IP: 99.6.8.35

7 Days To Die Resource Usage
================================================================================
CPU Used: 92.1%
Mem Used: 0.5% 649MB

Storage
Total: 20M
Serverfiles: 15G

7 Days To Die Server Details
================================================================================
Server name: 7 days to Die
App ID: 294420
Server IP: 0.0.0.0:26900
Internet IP: 99.6.8.35:26900
Server password: penis
Maxplayers: 8
Game mode: GameModeSurvival
Master server: not listed
Status: STARTED
Query Check: https://ismygameserver.online/sdtd/99.6.8.35:26900

sdtdserver Script Details
================================================================================
Script name: sdtdserver
LinuxGSM version: v25.1.6
glibc required: 2.27
IFTTT alert: off
Update on start: off
User: linuxgsm
Location: /app
Config file: /data/serverfiles/sdtdserver.xml

Backups
================================================================================
No Backups created

Command-line Parameters
================================================================================
./7DaysToDieServer.x86_64 -quit -batchmode -nographics -dedicated -configfile=/data/serverfiles/sdtdserver.xml

Ports
================================================================================
Change ports by editing the parameters in:
/data/serverfiles/sdtdserver.xml

Useful port diagnostic command:
ss -tuplwn | grep 7DaysToDieServe

DESCRIPTION PORT PROTOCOL LISTEN
Game 26900 udp 0
Game+2 26902 udp 2
Query 26900 tcp 0
Web Interface 0 tcp 2
Telnet 8081 tcp 1

7 Days To Die Web Interface
================================================================================
Web Interface enabled: NOT SET
Web Interface url: http://172.23.0.10:0/index.html
Web Interface password: NOT SET

7 Days To Die Telnet
================================================================================
Telnet enabled: true
Telnet address: 127.0.0.1 8081
Telnet password:

Status: STARTED
```

### Steps to reproduce

_No response_