@probablytuna: dude. That room is nothing but hidden doors. Press X (or A) on every surface around there. Then go to town.
Do you not unlock hidden passages by hitting them? No wonder I didn't find any. That's fucking wierd man. I did remember finding one wall my weapon would clip right through but I couldn't figure out how to open it, but that was probably just for use with the wierd pharoh key. But still fuck that shit man.