[com.triodos.bankinguk] Activating Mobile Secure Key fails

Affected app
Name: Triodos Bank UK
Package id: com.triodos.bankinguk.325

Describe the bug
The bank offers to the ability to activate Mobile Secure Key which replaces a physical DigiPass for approving payments etc. on the app. To activate the Mobile Secure Key, the user needs to upload photos of an identity document (e.g. driving license) and a video of the user's face. I was able to upload the photos of the identity document but at the page for uploading the video, the following error message appears "Please install Google Play Services to continue". I have confirmed with the bank that their app does not support microG, receiving the following reply "The Mobile Secure Key is not compatible with MicroG libraries; Google Play services are a pre-requisite for using the Mobile Secure Key."

To Reproduce
Steps to reproduce the behavior:

1. Download Triodos UK banking app
2. Open the app and log in
3. Click on Activate Mobile Secure Key under Feed
4. Follow the instructions
5. At the page where one has to take a video of one's face, the screen shows 'Please install Google Play Services to continue'.

Expected behavior
I am able to upload a video of myself and activate the Mobile Secure Key.

Screenshots
I took a log of the error that is split into two because of size limitations
part I
part II

System
Android Version: 10
Custom ROM: /e/OS1.5-20221031230909

microG
microG Core version: 0.2.24.223616-96 (f87cb98)-noen
microG Self-Check results: All ticked

Additional context

Start by reproducing the Mobile Secure Key activation flow on Android 10 with /e/OS 1.5 and the reported microG version, then inspect the two linked log excerpts. Determine whether the Google Play Services requirement can be addressed in GmsCore; done would mean the video-upload step proceeds in this setup, or the limitation is documented with supporting evidence.