Oh aye we definitely would be but leaving aside Slatts Oscar winning performance and the faux outrage, the rules are quite clear.
An attempted hand hit (punch or strike) on an opponent is generally punishable with a red card, even if no contact is made, due to it being classified as violent conduct.
So VAR seemingly correct in this instance.
Can imagine Slattery getting absolute pelters at training on Monday and SOD browsing Amazon for a replica Oscar statue.