Best way to pull is using south staircase. You will have to clear about 5 mobs along the way and might get one add. This is if you plan to pull him to a first floor camp.
Can confirm he spawned on the 2nd floor balcony. Unsure if this is a fixed spawn point, but can confirm what the other post said. Loc is -1579, 465, -63
Spawned twice for me on the second floor of the fortress in the south of the zone. He was on the "balcony" type area on the second floor, Southwest corner. Location -1579.97, +461.91, -64.07