If the cheap watch can get off for his late leg hit on Cherry and Thurston had no case to answer after a forearm and a headbutt then Foz shouldn't have had a worry. It was obvious that more damage was done when Gardner's head hit the ground than from when Foz hit him and he did get him around the shoulders.
BTW, being honest and without showing my Manly bias, if I was the ref I probably would have penalised Foz for that tackle. Not sure if it warranted being put on report though. But in the heat of the moment and the way Gardner went down (and with Foz just hanging his arm out there), the ref really didn't have any other option but to blow a penalty. But a penalty is all that should have happened.