What? a geri-chair? no way! thought this place was abandoned long ago, but friendly sight of the familiar geri-chair is somewhat comforting...lol

Actually, there are patient, or "resident" rights laws in place that make it a very long and complicated process to use physical restraints to reduce the risk of harm from patient to self or staff, but, when these buildings were in use those types of laws had not yet been created. If you are wondering what staff now do in a case where physical restraints are not appropriate but a solution is necessary, they use "chemical restraints", powerful medications which render patients subdued, calmed, or temporarily paralyzed.

the bars look slimy

There is a sub-basement yes, if you look on a stage, there's a hole in it that leads there. When you leave the auditorium, there should be a janitors closet on the right, there's stairs leading down into it there.