i was actually watching that auction. seemed like too much money for the amount of work it needed.
I don't think it was mold though.
i believe it was what people call "crt cataracts." before crts used "safety glass," people were worried about them blowing up and impaling them with lots of glass shards. they would laminate the glass to prevent it from shattering as catastrophically. these days the lamination is often peeling off and it looks like that. it's possible to repair and there are lots of videos about it on youtube. (i've never done it tho, and im kinda terrified of the high voltage.)
luckily they eventually started using glass that doesn't require the lamination, but an enormous number of crts from the right era have this same issue.
see here:
https://hackaday.com/2017/08/11/crt-cataract-surgery/
edit: i'll check out amibay too. thanks twolazy.

i missed your message at first ;;