Not true, in the Dublin v Monaghan AI Semi final this year...a Dub player went for a point (just inside the 20m line from a tightish angle) at the hill16 end, it was ever so slightly deflected off a Monaghan's player hand and went wide....the umpire and linesman signalled wide. The attempt was then shown on the big screen...Sean Hurson (the ref) then put his hand to his ear to cup his earpiece and then signalled for a 45. He clearly got a message down from the stands.
The guy next to me in the pub was livid with the decision. He shouted "You cant use video evidence to overturn a decision". The 45 was taken and the Dubs had another point on the board.