I think if your T is uncomfortable doing trauma work then they are without a doubt the wrong T to be doing it with.
I have seen 18 T's and Pdocs , 3 of which were senior consultants and only 2 out of the 18 were qualified in trauma work.
The right T is absolutely essential, and one who is unsure of their capabilities is definitely not one you need to be opening this can of worms with.
All the best.