substitution question

[me4tide]

1 out with runner on second. Coach calls time wants to put in a pinch runner for the#2 batter (who is on second). He tells umpire that #6 is the pinch runner but # 10 takes the spot on second. #10 was the left fielder and also batting in the 8th spot. Pitcher toes the rubber, catcher in position to to receive pitch, batter in the box ready to hit, and umpire in position to receive the pitch. Same coach then notices his issue calls time and corrects the players. Opposing coach is asking for illegal substitution. What would be the call in this situation under NFHS rules.

Umpire said he never put ball in play so it could be fixed without penalty.