If I am sitting in the cab, and press E to get out of the seat, I will be shot out of the roof of the cab. This only happens if you press 3 while underground to use the head-out camera before trying to get out of the seat (I think). Ignore the jumpscare that happens when I get back in the cab - that is probably a different bug entirely.
I am having the same issue and sometimes even getting stuck in the ceiling of the train all together. Any fixes for this?
The only workaround I found is to use Ctrl + or Ctrl - to swap cabs and then get out from the other side. Bit of a pain, but I doubt we'll see this get fixed.