Which is the erroneous free throw?

[Back In The Saddle]

Nearly had an unusual correctable error situation in a game tonight, and it got me thinking about how to correct it.

A1 is fouled on a shot, basket goes. Before administering the free throw, B1 is assessed a T. A1 is designated to shoot the T free throws as well. While I'm answering B2's question about the shooting foul, my partner erroneously awards two free throws for the foul. As we're about the administer the fourth free throw the potential mistake is brought to our attention.

What if we had shot the fourth free throw? To make it more interesting, what if the shooter had made the first two free throws, and missed the second two? That becomes important when you consider how to correct the error. In particular, was the second free throw the erroneously awarded one? Or was the fourth one the culprit? So would we take a point off the board or not?