I took these two pictures within minutes of each other. Maybe the balron spawn there is really that fast. I saw 3 die within a 2 minute span, but I cannot figure out how all of those non-summoned daemons got over in that little teleport-pit area. And, where did they go shortly after.
On that little area you can only get to by teleporter, there were 4 daemons. The guy and his 2-3 pals left. Then I left to bank, and came back (stealthily mind you) and they were all gone, no more spawn there. I don't think the spawn radius can reach that area, and if it did, the odds are very slim, and there were no corpses when I returned moments later.