If his foot was planted, then the ball rolled over his toe and did not really change trajectory (thus, he did not 'get the ball first', in fact he did not 'get the ball' at all). If his foot was not planted and he 'got the ball' because of that, then his leg was still in motion, and he took the player down as he tried to go around him.
You can't have it both ways.. And either of those scenarios should lead to the conclusion that it was a penalty that should not have been overruled by VAR. Those are the rules, no? The fact that VAR kept the ref there for multiple minutes to 'convince' him to change his mind should also lead to 'NOT A CLEAR AND OBVIOUS ERROR'
VAR is overstepping a lot. They have some legitimately correct calls with VAR, but too often, they are looking for the most ridiculous reasons to allow/disallow something.