@Paul Lannes Thanks for posting in our Q&A.
For this issue, I have done a lot of research. I find that someone has met this similar issue. He said that the BlockAADWorkplaceJoin registry setting caused this issue. Please refer to the following link:
https://www.reddit.com/r/sysadmin/comments/sd6sfx/windows_365_vms_not_provisioning_failing_at/
Note: Non-Microsoft link, just for the reference.
With Q&A limitation resource, if the above doesn't work, it is suggested to create an windows 365 online support ticket to get more accurate help. Here is the support link:
https://learn.microsoft.com/en-us/mem/get-support
Thanks for your understanding and hope everything goes well with you.
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