Quote please change my name to ="please change my name to "Although this has turned out well surely turning up and saying your sorry is better than just sending a letter?'"
He apologised in the letter, didn't he?
Only point I'm trying to make is, if you're accused of abusing an official, you either did or you didn't. You can't really expect the defence that "he gave lots of wrong decisions against me" to hold up, since that has no bearing on the case. To apologise by letter is good enough.
If he's been provoked by a player (smacked in the puss and this has gone unseen) and retaliated, and he'd been the victim of more foul play during the game that went unpunished, he might have thought it worthwhile turning up.