Substitution after a made free throw

[stewcall]

Was watching an AAU game with a NFHS ref officiating
2 free throws- the first is made- the official bounces the ball to the player just as the coaches attempts to substitutes- the official properly does not allow the substitution- the free throw is made (We now have a dead ball). The official still would not allow the player to enter the game telling the coach the player needed to be at the scorers table before he bounced the player the ball- I think he was wrong. He knew the player was there and there was a dead ball. Am I correct or not?
Stewcall
CVBOA