Wait, his name was "Onno Hoes"? Seriously? Hahaha.
Though his story sounds very Anthony Weiner-esque, so yeah I would say that he should have been fired, especially since he was using official social media for some of his activities.
Weiner harassed women by sending pics uncalled for, this is quite different. There doesn't seem to be any element of harassment or transgression.
He shouldn't have used an official account, but otherwise its a private matter. Hitting on young adults as a middle aged man is "optimistic", but not morally wrong.