The line was shot. I've seen a workprint of the film at UCLA, which includes this short scene, and Shatner flubs the take.
(Of course, it's a good thing Sulu wasn't promoted. If he was, he'd probably have departed the series.)
Can you verify this? I mean it sounds interesting and I am not calling you out, but as one anonymous person on the internet to another, this is pretty thin as far as evidence goes.