You mean how to ask your T if he would want to talk to your pdoc? Say that you find it so hard to talk to him, that you can't tell him anything and if maybe T can talk to pdoc about it?
Or start by asking him if you can ask him something. He'll say yes. You can ask him if he ever speaks to psychiatrist for clients. Say that you find it really hard to talk to pdoc and if maybe he would want to talk to him on behalve of you?
It's hard. I find it hard too to ask my T for anything. But that's how I would probably do it.

Or you can write it in an email to T, or a letter? If asking about it in person is too hard.