(((((granite)))) Dear one, your T knows how complex csa can be, and she can help you when you are ready to let her know more. Maybe that would be a way of bringing this to your therapy, saying to your T that there is more that you want her to know. Talk about that first, and about how you want her to know and at the same time you don't, because you have fears about how it could affect your relationship (with T).
To me, it sounds like you were trying to gain some control against your abuser who put you in a desperately vulnerable situation. This was not a 'place' where logic and fair rules applied.
I hope you can let your T know, whenever you are ready, so you no longer have to carry this burden alone, and so together you and she can explore it and understand more about what happened.