And Goblins that are in different room ... out of building ... hells, even far from that building (by the gate) ... will know when Dror Ragzlin is killed ... also telepaticly as it seems.
Not sure if intended, but i certainly hope not. :-/
I've noticed that too, but I thought this happens, because the goblins lose their leader. So they get feral again and attack everybody like before the Absolute came.
Did this happen to you even if you killed Dror Ragzlin first?
I've always killed him last so I thought that was the reason why they get hostile.