I was able to identify the cause and fix it for next patch.

Better late than never: This issue will be fixed with next patch :)

I basically deleted all wide doors in the entire level but not a single one got replaced with a wrong orientation:

My guess is, the issue was fixed internally by fixing another ticket, but the fix is not yet in the public version.
I'm closing this ticket as done as all tests indicate it is all working as it should.
So it should work for everyone with next patch.