If you head north from the "portals" room you will pass some "tents". To your right will be some ruins with about 5 girplans in. Keep going to another tent and ahead you will see a largish building at around loc 1200, 750.
There is one girplan immediately outside the doorway to the building and two more a little south east.
His placeholder is the eastern one of those two.
Aggro range here is quite large.
Only killed him twice so far and got one of each drop (plus one 68 rune). The second time he proced Girplan Chatter.