The man's a devout Catholic. He opposes changes handed down from Vatican II. There's lots of Catholics that do. That doesn't imply they reject the church as an institution or papal authority. It just means they really don't care much for the liturgy(there may be other things too). And, guess what? they are allowed to. I even recall John Paul II actually doing a Midnight Mass which was Tridentine and not Novum Ordu.
I might be mistaken, but I don't think Mel's "Old Catholic."
One of the first things JPII wanted to do when he first became Pope was to allow the Tridentine Mass back into the Church. He finally had time after he was nearly killed to get the ball rolling. The Tridentine Mass (pre-Vatican version of the Novus Ordo) is now said throughout the world. This is the Mass that Mel probably has said in his chapel.
Let me say, the words of the Tridentine Mass are absolutely heavenly.