If I'm remembering correctly we said they were going to find the list of Sith operatives in the library first, and their finding of the list would trigger a trap of some kind that would tip Renso/Bracknell off to them being there and their little brush up with him would ensue from there? O.O feel free to have somebody stumble upon said list in your next post :P 

Feel free to take any artistic liberties with the reason for the skittish hounds, maybe they can sense another power watching them somehow or it is just the fact that they don't like the place xD