AFAIK we don't know that the police "consider him innocent", we know that they never formally pressed charges. For all we know the worm heart struck some kind of deal where he rats on the kiddy fuckers in exchange for immunity for his puppy fucking.Literally what does Kero's full comment even have to do with the Zoosadism stuff.
Kero not understanding that police considering one innocent doesn't mean he didn't do the crime at all is odd.
Full on expecting Kero to pull the "I don't want uwu dwama connected to my name!" Card if he ever does tackle the DMCA question
More likely the cops didn't gather enough evidence in time before the statute of limitations expired, so legally they couldn't prosecute even if personally the cops think he's a puppy fucker.
In crimes with no statute of limitations, detectives are known to keep tabs on suspects for years waiting for them to slip up or stumble onto the final piece in the puzzle that allows them to press charges and hopefully prove it in court.