I found this Knight by accident. I was fighting the cabal and got backed in to the door way, I jumped up as one of the shield cabal hit me and it sent me up and in to a little hole above the door. I thought I was stuck, so I was jumping around and ended up on the opposite side of the door. I didn't have to do the console step as the door was already open. I slayed the Knight, got my emblem, did a dance, and left.