I've worked with Jetta Stone a little (same basic material as Corian)
I stop drilled a crack using a 3/16" bit, then "Veed" it out both top & bottom using a die grinder with a 1/4" burr. I saved the particles from the process, mixed them with the Jetta Stone bonding agent which I used to fill the vee area & drill hole. After sanding back level, the repair came out 99.9% perfect.
The color match was excellent on my repair however, it may not be spot-on depending on the color you're working with.
07 Hawk Conversion, Freightliner, 450MB, 10spd Eaton autoshift