I figured it was. I also tried out the newest GE-Proton (10-33 I think?) and it also wouldn’t start the game so I gave up and went back to Windows for now.

When other newer games came out like Esoteric Ebb or the Oblivion remaster/remake, it played just fine on openSUSE. It’s just one of those pain points that will generally never go away I suppose? :-[