I spawned him twice in this room. Both times he appeared in the closet with three rats. /Loc was 1006, 431, -607. Then I read the other posts. I'll give that a try.
Actually doesn't reset when room is fully repopped. Got him a few times after 2 kills, so someone obviously cleared it twice before me. 26 kills however, is dead on.
Finally got the reserve after about a year of random camping...definitely not a very well thought quest by sony, I still have yet to get the map, maybe next year I will get that