A collector number is not a print run

A number like 58/102 means card 58 of 102, and a serial like /99 means something else.

"58/102" means card 58 of a 102-card set. Every card in that set says /102.

A serial like /99 is stamped on the card and means something completely different. It says how many copies were made.

The {serial} token puts a real serial in the title. A collector number never goes there.