What should I have done?

[Zoochy]

I am the R2. Team A is getting ready to play their 3rd hit near me. A1 spikes the ball and 2 players from Team B jump to attempt a block. The ball catches nothing but the tape at the top of the net. The ball caroms back to Team A and they play the ball. I give a discreet signal of 4-Hits. I only hold it for a few seconds. I do not want the Coaches from either side to see my signal. R1 allows play to continue (I wonder if he ever sees my signal). Finally the ball hit the court on Team B's side. Point to Team A. Coach for Team B is upset. He complains to me about the 4-Hits. R1 sees this discussion. He give a signal, of rubbing his fingers, indicating that the ball was touched. I know the ball was never touched. Whether or not he knows I gave the discreet signal. Team B's Coach says, "You saw the ball was not touched. Make the call." I 'took the fall' and let the play stand.
How can I handle this situation properly without embarrassing me or my partner? I did not discuss this play after the match