Out of line?

[canadaump6]

I had this situation a while back in a kiddieball game with the good old no leadoff rule.

1st batter gets hit, appears okay, walks down to first. Second batter reaches safely, moving the batter who was hit to 2nd. Bench coach exits bench area and asks for time so I grant it. He asks if he can talk to his R2. I allow him to, believing that he is concerned about the health of his runner after he was hit.

I stand by the first base foul line and watch as he speaks to his runner. I can clearly tell that he is not making sure he is okay after being hit. As the coach comes back I say to him "what was that about?" in a neutral tone. He says to me "I was instructing him on not leading off. Sorry about that,".

Between innings my base partner told me I had no business asking him what that was about and that I was lucky this coach didn't tell me to get lost. According to the base umpire he had every right to speak to his runner because I allowed him to in the first place. I guess I shouldn't have assumed his reason for going out there was to check for a possible leg injury or something.

Was I way out of line in asking him "what was that about?" and what would have been a way to handle this situation differently?