when i first saw the video, i saw at the end she kind of shoves him in the room with her hand so she can get in and close the door.
What I was thinking was that her initial shove was just a lazy way of doing the scoot him into the room. She was just too much body mass and shoved him into the ground. It is hard for me to believe anyone would willingly shove a kid into the ground like that. Let alone a teacher of over 20 years and a disabled child.
Upon second look. It did look like some malice was present. If so (I still hope not) that is disguising.