Yes, the dungeons are randomly generated and this can happen.
I had in one of my dungeons a critical corridor blocked by a broken wall that I couldn't walk over.
You can't do anything about it, even reloading the game as the dungeons are pregenerated at the beginning of the game (I think). Or you can try reloading a game on an earlier act and seeing if the dungeons are generated at the start of every act.
Anyway, I know the feeling of frustration.