Oh Balance already hints at Gate Pass... "We ourselves left home twenty years past, passing through the Gate to the sunlit world, where we sought a home, a quest which eventually led here."

it is very well hidden, but Balance reveals quite a lot about the Trillith if you take their words implicitly. If you wish to name more Trillith, you could let Balance name Freedom, as she was one of the (if not the) first Trillith, and maybe Agony. Balance is a pretty old Trillith, so they won't know about the recent plans of their kin.