wookie doesnt mention anything about her ambushing him. according to wookie he tries to collapse the building on her or some shiz and she cuts a hole in the floor and uses that to escape, then they go downnstairs and he demands she join him, she stands across from him and says no, he tries to fry her and she runs up and cuts him down.
apparently, leia helps her by guiding her with the force or some shiz.
Let's try this again... 😛
Regarding the Mara/Joruus thing, this is what I was referring to:
http://img339.imageshack.us/i/joruus1.jpg/
http://img219.imageshack.us/i/joruus2.jpg/
Like I said, his attention was diverted elsewhere when she struck him down.