Tip with .2 seconds waved off

[Rufus]

But I do know that in HS we would make sure, either in discussion during the dead ball or signal by the appropriate official, who had last-second shot like that. Only if the other two had definitive information contrary to the calling official's take on the play would they go to them and let them know what they saw.

All that being said, why are all three officials making a call in this case? Shouldn't it just be one?