I don't think that therapist "specialists" are really necessary much of the time. And one's assessment of how experienced someone is with something that is really common like overeating issues may not be accurate. Very little therapy is the product of academic knowledge and probably not even training, but more experience and skill.

You don't have to magically figure out how to "talk better" or explain what you need. You can ask your T to help you figure these things out and have a conversation (or 100) about what you are finding difficult about your therapy and what you need. This is a big issue in and of itself that most of us cannot just produce on our own. I'm glad you trust your T to help you work through it. Good luck.