Its exactly the same thing as I showed in the 15 second video I made. I passed the reflection of my hand in front of the reflection of the flashlight I used. I did not use my hand to directly block the reflection from the view of the camera, that would have proved nothing.
I guess what you missed is that you can see the reflection of his hand in the window and it is that reflection of his hand that passes in front of the light and the light remains that PROVES it is not a reflection from the inside of the Aircraft.
If the guy had been "crossing his hand directly in front of the light" from the cameras point of view, the light would be blocked out either way and would prove nothing! What he did actually PROVES something.