This zone goes back a few years, but trying to clean up some old quests/achievements. In Wing 1, I have cleared all except for Grendish - he appears as a flying NPC that is non-attackable. I remember from the Heroic version of the zone, you would have to clear certain mobs for him to be attackable, however, I have cleared his entire room and still nothing. No other Wings of the Temple are open and accessible now until he is killed - any help from some raiders who recall what to do? Google and the interwebs haven't helped me yet.