Here are some more pics for your viewing pleasure. I opened up the reservoir and cracked open the pump.
If you notice, a little piece of the impeller broke off. Now this makes me think that the killcoil may have lodged itself in there, and caused the pump to overheat and explode.
I just saw another active thread where the killcoil killed the same pump. However, when I disassembled the system, the killcoil was near the fillport, just as where I dropped it in from day one. I also have the standard killcoil from frozencpu, which is pretty large, but it does fit under the pump and could float over to the other side. I could not find the piece of impeller that broke off. Maybe its stuck in the radiator.
The pic of the pump motor shows great damage. It's amazing that the power this thing exploded with was enough the blow a section of the 3/16" thick reservoir roof. I had to use a chisel and hammer and some good force to crack open the reservoir.