I really hate hearing this. I'm sorry for you and how you're feeling, but even moreso I'm sorry for that poor guy. I know how he felt. All of us do.
You, my friend, are in a very good position here, because of your profession. Without casting suspicion on yourself, you can freely rebuke those who speak ill of this man, in the name of Christ. Jesus would not have spoken of this man in such a way, nor would any "decent" Christian. Well, really, nor would any decent human being, but those are in short supply these days.
I encourage you to handle those horrible mean-sprited people with rightious and measured indignance. If anyone can get away with it, it's a man of God.