The Drunken Lizard Pub

Well sorry to say but, no, I don't see those switches, is it possible there's a corruption code?

OK so I'm in the Goblin Citadel, I've gone through nearly the entire first level, I've worked my way to the gate which has a pressure plate under it, so that if I try to go through it, it kills me. How does one get through it? If I first have to get into the spider room, I'd really like to know how ...