State Championship Game mess up

[Moe]

Official calls a foul on the baseline on team A. 9th team foul and teams line up for 1 and 1 by team B. As the teams line up the other official who is admistering the free throw indicates two shots at the same time trail official is holding up the 1 and 1. I'm not sure if he thought the foul was in the act of shooting or that there was 10 fouls. Shot goes up and player from team B grabs an uncontested rebound and makes a basket. Whistle blows and player start to argue if it was two shots or 1 and 1. My question is what do you do now. The officials in this game got together and decided to take away the basket and go to an AP arrow which had team A getting the ball at the baseline. Was this the right proceedure.