I'm impressed that folks on here know exactly what the R saw . . .
The R did what he is supposed to do: make a call based on what he saw or didn't see. Here he believed there was no foul. It is not the R's job to second guess himself. The VAR is charged with recommending a review in the case of a clear error. The R will, in appropriate cases, share what he saw with the VAR. But if there was a clear error and the VAR did not recommend review, that is 100% a failure by the VAR.
As to ARs, no, that's not at all what ARs are doing. ARs are instructed to make calls exactly as they would have without VAR--the difference is they wait to raise the flag until an immediate scoring opportunity passes if it was a close decision. They get evaluated on their calls--if they raise the flag "just in case," they will get dinged for wrong calls.
This is not true. If the VAR sees a clear error--the standard for review--he is obligated to recommend an OFR to the R. Any signal the R made is totally irrelevant. VARs get evaluated on what they recommend to be sent down and have every incentive to do it properly. (And Rs who reject the recommendation to do an OFR will get evaluated on that decision, too.)
IMO, this is a horrible idea. VAR is not there to make the game perfect. It is there to fix clear errors. There has to be a call on the field. And what do we call as refs if we don't see a foul? Nothing. The same is true for us in our lower level games and for the pros doing the top flight games with VAR.
Why does there have to be a call on the field? Why can't it be I don't know, help me out?