Problems w/ MARS on Azure Virtual Desktop host

Greetings,
I endeavor to perform file backups on the "C:\Users\Public\Public Documents" folder of a Windows 11 Enterprise multi-session virtual machine hosted in Azure.
Yesterday I configured the machine via for an On-Premises\Files and folders backup via the Recovery Services Vault and everything looked great, but after last night's first scheduled run things are not great.
In Azure:
In Backup Items (Azure Backup Agent) the "Last backup" is grey with a hyphen, not Success or Failure.
Clicking the details of the Backup Item shows a recovery point as expected but again the "Last backup status" is grey.
On the virtual machine:
Microsoft Azure Backup won't load CBSnapIn.dll reports "MMC has detected an error in a snap-in and will unload it" - event details attached.
(At least I think the event details are attached, I clicked the paper clip and uploaded the file anyway)
More Info:
In uninstalled/reinstalled MARS and it ran and I was able to mount and restore from the back up.
Subsequent attempts to run MARS failed (same error); I wanted to initiate a "Backup Now" but was unable.
Any ideas?