For it to fire, it would have to land directly on the primer. That means the shot would be 90 degrees straight up. Not at a 70 degree angle toward the corner wall.
Again, it is quite telling that he rolled the shell toward the others. Anybody who has handled shells/bullets on a table doesn't roll them around unless you WANT to get on your hands and knees and root around on the floor to gather them up. You either put them in a tight pile, or in a container, or stand them on end.
WHAT IS THE PURPOSE OF SHOWING THE PRIMERS AND SHELLS TO THE CAMERA WHILE MUMBLING??
Again, I am sure this is a staged fake.