Crash at loading screen, due to corrupt save file.

What if you disconnect the machine from the internet then start and make a new campaign save?

Then that should be the latest.  

It overwrites your newer save with the older ones synced down?

If so I can't think of another way around this, I have to say! The MS/Gamepass infrastructure is particularly opaque , we have no visibility into it.

I guess if you made a new Windows user and logged in as that, the problem would just transfer over, is that right?