Well, yes, I've noticed it happen occasionally... in general, I am deliberately trying to lose grapple matches (so that Hiro gets it in the ass, LOL), but some enemies appear to be unwilling to take advantage of it and it sort of results in a stalemate
No, it's in adventure mode. Try to run past, then agree to play Mino Mommy's game and keep trying to find your way out until offered an option to "settle down" (which will lead to game over). Be sure to fail any stats checks and not actually take a chance to escape if presented with one.