Yes, and the last thing he should have done was to lay it all off on the caddy. A class act pro would have said, "The ultimate responsibility is mine. I should have been paying closer attention to the time". Mind you, I like Dustin, I think he's a great kid, but obviously he still has a little bit to learn as far as how he carries himself in front of the cameras.
There is just no excuse, other than an emergency, to miss your tee time. On every putting green, at every tournament these guys play there is a gigantic Rolex clock. To miss your tee time says you aren't focused IMO.