First just getting the balll inflated is difficult--hard to get it to hold air.
Don't know how the trainer was chosen, but she looks like she should have used the ball for a while herself before telling us how good we are going to look.
Did you look at the rip in the side seam of the shirt of one of the participants?
The trainers abs and the rip in the clothing just don't appear very professional to me.
Nevertheless, I am going to try the exercises and see if they work.