Correctable Error: Incorrect Information by the Game Official.

[Nevadaref]

Originally Posted by just another ref

No matter how many players try/don't try to rebound, if the official didn't count the basket and announced two shots, this is a free throw which is to be followed by another free throw. When it comes off the rim, this ball is dead.

You can certainly argue that position, but you will be fighting several NFHS case book rulings stating either that the officials mistakenly allowed the ball to remain live following an announced first FT or that the officials shall whistle the play dead. According to those rulings the ball doesn't automatically become dead if the officials aren't diligent. It certainly doesn't become dead if both teams attempt to rebound despite the erroneous information provided. That ruling is posted above in this thread!