For what it is worth, I have never had a t tell me about their qualifications directly. They have told me about their methods and have been very willing to answer questions about them. One t has her diplomas on her wall. One has told me where he went to grad school. And one I have no clue about.

If you want to know, I think it is ok to ask. Especially about their method. It seems like asking about that is just taking care of yourself.