End of Half situation

[Jimgolf]

Ironically, I watched a boys varsity game last weekend where the same thing happened, except that there were no shots to be taken (player control foul). The coach apparently said one of the magic words on his way to the locker room, and a rabbit-eared official T'd him up. They took the shots right then, not waiting for the third quarter. Two varsity officials I asked later that weekend said this was the correct procedure. From what I see here, this should have been done at the start of the third quarter.

Would this be considered a correctable error, had the coach known the correct rule? (The shooter made both FTs, so perhaps he might have wanted the shots taken again in the hope one or more would be missed.)