If you're on good terms and probably also in a friendly situation, you can discuss the parameters involved and go from there.it just seems not right to me to have a shot you cannot see if it a good hit or not and allow it to be shot. and then call a foul not because you saw it but because your interpretation of how the other balls reacted means it was a bad hit.
if going to try and do that then it is mandatory to explain and agree upon that way of deciding before the shot not after.