8th grade tournament game(2 officials) at a neutral site this afternoon end of the 3rd Q. Ball stolen by B1 as time is running down, I'm new lead running about even with the ball when B1 takes a running jump shot right around 3-pt line. He had enough time to take another dribble before clock ran out and he surprised me when he pulled up earlier. I never saw where he left the ground so I couldn't help my partner with whether it was 3 or not. Partner originally signaled 3 but questioned whether it was 3 or not. I know I should have had a look at it and been able to help, but i had to tell him I had no idea. My partner is a 20+ year veteran and decided to ask the clock operator(impartial not associated with either team) what he thought. He thought it was a 2 pt shot, so we went with a 2pt shot.

My question is, Is the clock operator or table a tool that we have in this situation or should we have gone with my partners original call of a 3pt shot?

Please give me a rule reference if you have one.

Thanks.