The only VAR games i've seen are internationals so i have limited understanding of how we'll use it. My working assumption is we'll copy England wholesale. I hear bad things from English types, but most of what i've found out about VAR is from the protocols and not anything in practice.
What i was meaning was that that decision wasn't a question of whether there was a dive without any contact (i mean there was a dive, but also a wee tug), or whether the ball hit a defender in the hand or face or something. The ref knew he'd given a professional foul 45 yards from goal. Confirmation bias suggests he's going to see the replay and decide that the other cb wasn't going to get there, whether or not he was.
The onus of proof is that the decision has to be clearly and obviously wrong. So he'd have to think that it was clear and obvious that the other cb would get back, rather than there just being a very good chance.