Your reaction to someone faking a result on you if you're town should be immediate and wholesale rejection, you don't have to think about the logistics of him being modblocked because you know a priori he can't have anything.
Instead you're being cute and trying to defeat the merits of his "claim" before he even has one, which is a nervous reaction.
You also haven't bothered exploring why he would as scum come in and confidently fake a result on you