Mike,
If you are missing the element in your glow plug it is what did the damage. I did the exact same thing to a KBV .82 after a too lean run. My first deadstick in over 100 flights. I sent it to Ackerman and it was only $85 for the repair, I don't know if he replaced the head or just polished out the surfaces. He also replaced the bearings.
Yes, your glow plug element did the deed.
Sparky