Look at the tiny mound of sand that was behind his ball when he addresses it. Then the head of the club dips one, two, three, and then four times. After the fourth "dip", it's gone. Clearly visible. And interestingly enough, no more dips once the tiny mound was gone, but an almost immediate swing. Hmmm.
IMO, intentional. He knew that any sand between the club face and the ball would alter the trajectory of the ball, so it was a deliberate, but very smooth way to try and tamp down that sand. He just got caught, or if not intentional, just screwed up. Either way, two strokes.
One of the popular golf magazines has a regular feature titled "Undercover Pro". It's an honest, sometimes funny narrative of what goes on inside the Tour. My guess would be it's a middle-of-the-pack tour pro who has good talent with his golf game, and serious talent with his words.
Bottom line: PGA Tour players cheat. Some of them don't, but most of them do, and some of them are always looking for an edge. And there are some "serial cheaters" on the Tour. No names were given, but still....
This one got caught.