What would you do?

[Ref in PA]

I am doing a spring league for girls varsity and last Thursday a situation came up that got me to thinking.

We had a three man crew. I was the C and the ball was in the opposite corner. The L called a foul on B1 in the low post. About the same time A2 starts her shooting motion in the corner and swishes the shot. The L came out strong on the foul call and waved off the basket, but in reality, had no clue when the shot started (rule being if the shot motion has started, then the foul by B1 off the ball, the basket should count). Now, as the C, I had no clue as to the timing of events because I was opposite side, concentrating on action off the ball. However, the T should have had a good view.

My question is, when the L comes out and whistles the foul and waves off the basket, what are "best practices" in that situation? Do we remain quiet even if we are 100% sure the shot should be counted?

In my opinion, the lead should come out strong with the foul call, but wait on waving off the basket until a partner check can be done. So, I fault the L with bad mechanics here. But once the L does that, do we eat the call? How would you handle it?