When can the C make an over and back call?

[iref4him]

I am working on a 3-man crew. I am the C and the ball is in my primary just above the free throw circle extended. A1 is dribbling the ball with lots of pressure from B1. The ball deflects off of B1's foot and then goes off A1's foot into the back court. (THE BALL WAS IN MY PRIMARY). A1 goes to get the ball in the backcourt. I whistle the over and back. The T comes over and explains to me that over and back is his call to make and he did not see the ball go off of A1. He wants to give the ball back to A. I asked him where he was looking? I thought the ball was in my primary. He said it was, but he has the responsibility and it is his primary to call over and back. I said I am not going to argue with you, but the ball was in my primary and it did go off of A1 last. He then invoked the I am the Referee for this game, it's A's ball. I believe C can make an O&B call. Does anyone else?? Or am I mistaken.

(By the way, we gave the ball back to A and discussed the situation at halftime. He wouldn't back down from his position. I had a whole another half to work and did not want any animosity on the floor.)