My man you can't be flashing high schoolers
(1) Has he experienced an appropriate amount of retributive / vengeful justice for his crime?
(2) Given his current state, what are the chances of additional, problematic offenses in the future?
IMO the prison time probably satisfied (1). So the real question is, how can prospective employers decide about (2) at this point?
Come on, it's not like he was waving his todger at five year olds. Seeing a spot of unexpected nudity at 17 years old is not a big deal.