From what was written, I'm not so sure the wave off was not the correct call anyway.
You described contact on a dribbler that you saw and
then he got in a bunch of players and you lost him.
That sounds like the dribble was gathered after contact.
Your partner said, "The gather occurred just as or slightly after your whistle," again that clearly suggests a foul on a dribbler, not a shooter, since there has to be some reaction time for you to blow your whistle.
I'd say that not only shouldn't you wave it off and then change it, but you changed it to what sounds like the incorrect call.
