um, its speculation and you know it.
yes it implies something happened to him. its a very telling line. but assuming it was caused by the the mob is just that: an assumption.
to me it looks like the left side of his face was involved in some kind of accident and he gave himself the cheslea scar on the right side to match.
bottom line, by leaving it up to the audience, crook can believe it was the mob, i can believe it was a baking accident, and johnny two shoes can think he messed up his own face. its unknown.