Cannot deploy Custom backgrounds for Teams in VDI environment

We have detected (or so we think) a malfunction in Teams on VDI when attempting to deploy Teams backgrounds that should be available to users for their video calls.

The only article that documents how to do this is the following:
https://learn.microsoft.com/en-us/microsoftteams/custom-meeting-backgrounds

It clearly states that the path where custom Teams backgrounds are stored is in the user profile, specifically in the folder:

%LOCALAPPDATA%\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams\Backgrounds\Uploads

Expected Process

The process is not direct, but it is straightforward. Using a script, a UUID is generated, which is used to create two image files (JPG, BMP, or PNG format, depending on the original image). For example, if the original is a JPG:

1. UUID.JPG
2. UUID_thumb.JPG

These two files are copied to the path above, and on the next Teams session startup they should be available to the user.

✅ This works correctly in physical (non-VDI) environments. Tested many times without issues.

What We Have Observed in VDI

1. Even when the file pair is copied to the correct path within the user's FSLogix profile, the image does not become available in the Teams client — even after restarting Teams multiple times or even the VDI session itself. After each restart, the files are confirmed to be persistent and located at the correct profile path.[ %LOCALAPPDATA%\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams\Backgrounds\Uploads folder contents]
2. When a background image is added manually through the Teams UI, a folder is created in OneDrive called "Microsoft Teams User Custom Video Backgrounds".
3. If additional images are manually added to that OneDrive folder, they do not appear as available in Teams. This leads us to believe that the upload process performs additional operations in the registry or other configuration locations beyond simply copying the file.

A ProcMon capture was performed, but after an initial superficial inspection, it was not possible to determine exactly what is happening under the hood.