What a year.
. Really sorry to hear about this latest misfortune. I've been following along with all the ups and downs. I've alway been impressed with your approach to reefing, and the time you take to document and share the highs and the lows. That you haven't immediately taken a sledge hammer to everything aquarium related in your house is yet another sign of your patience and passion for the hobby. Once the literal and metaphoric dust settles I'll be anxious to see what your next project will be.
As to the contaminates, I agree that the glaze may be the culprit. There are some really horribly toxic substances used in some paints and glazes (cadmium, etc), in addition to a myriad things that would not count as super toxic to humans but would play havoc with a reef.
Again, very sorry for your loss.
- Ian