You might consider a aluminum heat bed with a regular piece of glass on top. Look up heat beds on reprap and see how the diy community does it. They are cheap and easily replaced. I just print on the aluminum with painters tape. Sorry that it fractured like that, it happens. So having the glass glued down is not a good plan.
Built by the owner of a greenhouse in a suburb of the city where you could prohibit the sale of land to blacks. They ended up buying 2 more lots and building two more houses. USA, Michigan. Sadly, the title still states that the property cannot be sold to a black or mixed race. Its no longer legal, but the title says it. Other than that, its built well. Almost all the stuff done to the house after the 70s is garbage. Ie. Vinyl siding, replacement windows, counters, plumbing.
It might come loose if you heat the heat bed. At least soften enough to pry it off. The other option would be to finish breaking the glass. Then you could use acetone, or something to remove the glue.