If he doesn't voluntarily leave the team, he's going to create a big distraction next year, and probably split the team to some degree (I can't imagine with 84 other scholarship players that some aren't going to support him and some be pissed he got Leach fired). You can't just cut him, but you really don't want him around either. And if both he and the current WR coach are still around next year, that's going to create another uncomfortable situation.