thanks for your comments.
Since the fader has not mentioned his religion as the cause of the problem, I am reluctant to bring it up.
A personality issue would almost be easier to deal with since at least we could talk about each person's style and apporach to work matters and how it effects the work product.
I will need to get the fader to be specific and then address each instance with both of them and point out how the interchange between the two should have occurred. I will impress upon the dub that she does not have a choice in how she interacts with the fader concerning business issues and I will document the converation.
Unfortunately I believe that the fader is feeling somewhat guilty for his actions (whatever they are) and he has tried to work around the problems without alerting management.
Bottom line, I need the fader to come clean about his treatment and then I can deal with the dub head on. Without his side of the story, and his work product going downhill fast, I would have no choice but to deal with him in disciplanary way.
By the way, the dub is the most inflexible person I have every met.