I had one similiar to it in a boys game last Monday. You're best to judge that the foul by B1 caused the PC foul. That's what I did, but mine was easy to sell since the foul by B1 was a riding handcheck in the back.
But if you rule the other way, it's a FDF. There's no basket if A1's shot goes, A1 gets 2 shots with the lane empty, and then B gets the ball for a throw-in.
Oh, and you'll probably have to explain it to both coaches.
