I was just walking around roland's place (i don't know the exact name of the place) where the vault is and there's a cell with a chest in there. I press the button but it doesn't open it up. How do i open it up or do i need to just keep playing?
Look at the ceiling; there will be a couple of red pipes. Find a way up to them and walk across them as if they were a bridge all the way to the end, and there will be a secret room with switches to open the jail cells.
There's also a vault symbol in that room that you can activate, and it'll say "1 out of 2 hidden vault symbols found" or something.
he's describing how to open prison cells in a different area that has a chest behind it. You're talking about the one in sanctuary. I still don't know how to get to that one, I imagine at some point it might open up in a story quest.
When a true genius appears, you can know him by this sign: that all the dunces are in confederacy against him.