[just another ref]

Originally Posted by BigCat

That is certainly the general rule but when errors are involved you need the whistle to tell you what to do and what you can do. Ex. A1 fouled in act. awarded 2 FT. One shot and missed. all forget a second shot due. B rebounds, goes down and scores. Then whistle blown, error recognized. It is correctable but we know the basket by B is not cancelled. Points scored before it recognized count. If A would have inbounded the ball after B basket the error wouldnt be correctable at all. B basket counts and A doesnt get its other free throw. All of this even though a free throw to be followed by another was missed. The whistle matters.

What you describe is failure to award a merited free throw. This has nothing to do with the OP. In the OP, a player mistakenly grabbed a dead ball and put it in the basket. At this point the officials stopped the action and rectified the situation, though in my opinion more mistakes were made at this point.