Also. the blue marble face is illuminated from our point of view, which must mean that the sun would be in front from our viewpoint. Why didn't the moon cast a shadow on the earth as it was moving across it?
I'm not saying that the video is real because I have no idea, but my guess for why the light reflects back towards the camera would be that it is doing the same thing you see during sunset by the ocean. Wherever you stand by the water, the light from the sun looks like it is pointing at you. In reality there is light everywhere reflecting off the surface of the water, you just only see that which is directed towards you specifically.
If you look at the video, the lower left portion of the earth is brightest, and the upper right is dimmest. That should show you better where your light source comes from.