unreported sub question

[umpharp]

Second game of JV High School DH.

I'm on the plate in the 4th inning. After a base hit, Def. coach informs me that the player that just hit was never reported. I check and he was right. I go to the offending coach and tell him and he says, " The other ump told me in game one that I didn't have to as long as both benches know."
I checked with the def. scorekeeper, who was at the other end of the bench from the head coach, and she said that the other coach did tell her the change. I also checked with my partner and he said that he did tell the coach he didn't have to report the sub.
This guy was a piece of work, but the other stuff isn't relavent to the post.

This was high school, so there is no real penatly for the first unreported sub. I told the coach that I needed the subs and we had no trouble the rest of the game.

My question is if this was ASA ball or a second offense in a High School game, would you DQ or restrict the unreported sub? or would you give the coach a break since he was told by an umpire that he didn't have to report the sub?