Substitution on throw in position

[derwil]

Had this one last night:

Foul on Team A on a drive to B1 just outside the three point line. I have the whistle from T and indicate ball to the sideline. We were in Cadillac so I have throw-in responsibilities. After reporting foul, A2 subs in for A1 and as I turn to look at the player going out and to ID where the ball is when I notice U2 lining everyone up for a baseline throw in. I get U2's attention and tell him we're on the sideline and he throws the ball to me. Coach A then tells me that he subbed in A2 for the express purpose of a baseline throw in and now that it's a sideline throw in, he wants A1 back in the game.

No time ran off the clock so I didn't allow a re-sub. His subsequent play resulted in a layup so he was happy, but he could have really made a stink about it.

Would you have allowed the re-sub?