Um, that I'm not really sure. Mine have always been on rollers or cabinet liner. Possibly spray a little warm water, let it set for a minute and slightly wiggle to see if it will gently release? Or possibly coconut oil?
I had one hatch like that my very first hatch(her egg got caught and she pulled). Healed and fell off 2 1/2 weeks later or so. High hopes for the little one!
Oh wow, 12 years? I call that getting your money's worth these days. Hmmm, I'm not familiar with that one. I'd give it a couple more days if you see movement. If I remember correctly still airs have to run a little higher temperature, I wonder if it plays a role at all?