German Cockroach nymphs...freaking out, lots of ?s?

German roaches like to get in cracks and crevices under the cabinets and other places. And behind the sink underneath the cabinet. They have gotten immuned to sprays and about everything but Combat gel bait. The babies are immuned to the spray, that is how they can go through the spray. The roaches eat the bait and go to the hiding places and die. the other roaches eat the dead one and they die. The babies eat the fecis of the grown roaches and die. Gross, but they are roaches. That is how to get bait to the ones in their favorite places.