The maze levels were cut back before release, particularly the second one. It was easier and safer to leave the cut content blocked off than remove areas and NPCs during the balancing phase.
That room with the 4 skeletons is the end of the second maze level, so the area you found must have been stuff that was cut (it also doesn't sound familiar, but it has been a while since I played). There is just a short section after that until you get to the citadel, and after that is the end of the act.
