This was the last named I killed for the Hunter Achievement and it took quite a while. I just cleared every escaped sarnak and oracle and eventually he spawned at 1390,1284. The spawn info at the top here is very misleading in implying a single spawn spot. Not true. I suspect, as others have pointed out, that every sarnak is a placeholder, or perhaps every sarnak oracle. I killed them both to be safe. Thank Karana for tracking ability as they spawn everywhere.
BTW, the escaped sarnaks are very spell-resistant. Even at 115 I had to cast 4-5 spells sometimes to kill one, where other trash mobs of the same level frequently die to one nuke. This could be a real pain if you're tackling these mobs at the intended player levels for this zone, 80-90.