Basically you have to avoid a runaway reaction with these guys. Usually I hear about it happening on 10, though, a bit uncommon on 5.
Anyway, basically anything that dies on the planet counts towards the generator unless it died from the devourer golem or another enemy-to-all minor faction (that isn't Dark Spire). If you have advanced logging on the dark spire log will tell you what gave it the points and how much per unit, etc. It's possible something in your case was counting more than it should, maybe the wasps, though I think I handled their case.
I do need to give it some kind of release valve for spawns past a certain population to avoid it killing CPUs