This is possibly a dumb question but I wanna go ahead and ask, I know patching out bugs is allowed, but would patching in instructions be considered ok, or would that be considered a feature?  I know making a tutorial stage would be way more than a bug fix, but like a popup or something, would that be ok or would that be against the spirit of the competition?

That doesn't sound like it would impact any of the voting criteria. So it wouldn't make it look or sound better, it doesn't introduce new gameplay mechanics or directly make the game more or less fun so I think this is fine to do. If you've put in the effort to create a game the least you can do is make sure players know how to play it.