The two places this mob spawns is the "Statue Room" and the "Crusader Room" they would be room 9 and 4 on this map - http://www.allakabor.com/eqatlas/dalnir3map.html
Be aware these two camps are separated by a 1 way wall forcing you to zone out on the 3rd floor to go back to the statue room. Best to do this camp with a box and camp both spots.