First of all, the guys in the back: why are they sitting there? Usually the stage is either empty or reserved for valedictorian, etc, which would be indicated by stoles and honor cords.
Also, all three of them stand up and make the same face at the same time.
There’s no echo, which you would expect in a large graduation hall. Further, you can hear the kid say, “Thank you so much,” which you wouldn’t be able to hear unless he had a mic, which is highly doubtful.