I think Ake's goal was offside as Akanji was close enough to the flight of the ball. However, Leno reacted to the header and I don't think he was distracted by Akanji, he was just slow to get down. - Or perhaps it was a bloody good header, but why praise Ake?
We need VAR officials to explain their decisions for subjective calls such as interfering with play and red card incidents. I know they often appear to get things wrong, hence the apologies, but at least they are qualified refs unlike Marco Silva and the vast majority of pundits.