McGillvary's lawyer Nick Ghabar suggested it may have been because he had seen the footage and had second thoughts.
"I didn't bite his arm," McGillvary said via video link in Perth, where England will play France on Sunday.
"This is outrageous. I've been a professional player for 10 years, my discipline has been outstanding, I've never been charged or had allegations like this against me.
"For this to come out like this, it's outrageous and very disappointing. I'm not that sort of player - never have been and never will be."
McGillvary said he could not breathe after Farah had covered his nose and mouth with his forearm. With Farah's forearm already across his mouth, McGillvary argued Lebanon hooker Michael Lichaa completed the "grapple tackle" when he came down on the back of his head with his forearm and elbow, which drove Farah's arm further into his mouth.
Despite it only being a couple of minutes after half-time, McGillvary said he was already fatigued and ''I'm not the fittest player".
A written submission from England's club doctor Chris Brookes said a photo of Farah's bite mark was consistent with a "forearm being inserted into a mouth" rather than a bite.
Rugby League World Cup prosecutor Peter McGrath said the photographic and video footage proved there was a ''small bite".
"You made a deliberate motion with your head and mouth on player Farah's forearm," said McGrath, to which McGillvary said: I would say that's false."
McGillvary leant over and let out a huge sigh of relief when the verdict was handed down while coach Wayne Bennett cracked a rare smile and patted him on the back.