Yeah, he did. It was Robert H. Knight of the Family Research Council after a discussion about gays and the Boy Scouts. I couldn't find the story on rotten.com but I remember hearing about it in the "legitimate" media when it happened.
I don't know anything about any of these people but having read that articles linked above, my thoughts are that Bryant Gumbel was not exhibiting prejudice against Christians in general, just calling one particular one a divvy. One who was advocating homosexual prejudice.