This coral is significantly harder to cut through than real bone. You’re right about maybe needing a stronger operator thoughHave you tried calling one of your orthopedic surgeon friends? They have the real bone cutters, and the strength to use them.
Stylos are tough. Drain and dremmel is a for sure way that won't send you to one of your peers for a shoulder mri.
I've used the dremel extension and it works for a day, then rust binds the tool up so treat it as a single use.