The cancel pattern is a Paul-Son cancel, done in their shop.
They are more than likely over runs or mistake chips, canceled and sold in the PS retail store.
A box of them are usually too many to be floor sweepings, but if other kinds of chips are in the same box, they could be.
Fitz could not use them on the tables and be gaming compliant but stranger things have happened.
Be care of retired dealers. They tend to tell you what you want to hear. Been there done that.