I'd been down there already. I figured it out, in the room with the hanging cages I had to jump from cage to cage to reach the ledge on the other side, crawl under the pit of corpseaters to retrieve the lever and allow me access to the next area
I know this game is still in very early development but I'm getting the feeling like this is just the same game as agnietta but with a new lick of paint. Minus the animated scenes of course. Not to say the game is bad or anything, just an observation