Thanks Darryl, this is a fiberglass panel, not carbon. So not quite as stiff or strong and any delamination damage is quite a bit more obvious.
I did a layup of approximately the same thickness as the panel blank from Schempp Hirth. It's made out of about 6 plys of Rutan 7725 bid cloth that I had lying around (a decent cloth, but surely not what Schempp Hirth used) and US Composites laminating epoxy which is quite a bit lower grade than the MGS epoxy the factory used. I'm sure also mine has more air bubbles than what the factory made.
One of the shops suggested I bring that and do a trial cut and see how it turns out. My guess is if it would cleanly cut a laminate with weaker epoxy and worse craftsmanship, it'll probably cut the real thing well.