backcourt violation?

[sc/nc ref]

I am the trail in a 3 man crew of a Varsity Girl's game last night. White team has the ball in their frontcourt, running their half court offense. White1 attempts a pass to White2 near midcourt. The ball is deflected by Blue1, and then deflects off of White2, and goes into the backcourt. White2 then goes to the backcourt and picks it up. I call a backcourt violation because: Team Control- White, Last to touch it in the frontcourt- White, First to touch it in the backcourt- White. = Backcourt Violation.
I was calling with 2 "veteran" officials of 20+ years. The lead official comes from the endline, and tells me "ball was tipped by blue". I told him that I saw that, but that it was then tipped by white before going to the backcourt. He said that because blue tipped it before it was tipped by white, that it wasn't backcourt. The referee came over and agreed with him. Thinking that maybe I was missing something, I let them "punk" me into changing my call and giving the ball to white. Before the boy's varsity game, we talked about the play in detail. Both said they were positive it was not backcourt. Help Please!