ChrisHarris4!
You are a masochist.
Format C: is for dilettants on my opinion. If a Microsoft technician chooses this extreme solution it means, that they do not know the real cause of the problem.
For teh "format C: "solution you do not need any specialist, only have a good backup.
Ha! I'm not sure it was a format c: as my files were still intact. As it was done remotely I can't be sure. I watched the actions of level 2 and saw them find rollback in the log and the line above was referring to drivers. I am only guessing but he did mention drivers so I suspect that was the root cause.
My message to Microsoft would be rather than test the drivers half way through a big upgrade please do the test first and inform the user that there is an issue before repeatedly resending the upgrade and eventually destroying the code.
How about an optional patch/fix for those stuck on 1709 that surveys a pc for prereqs? After all, they do that before Windows 10 is first installed on a PC.