I would move the tee forward a few more inches. You want the ball even with (or near even) with her front foot after her stride foot comes down if you are working the tee up the middle which it appears you are.Here's one more. Sorry about the lighting....slow motion made it grainy. But, the tee is towards the front leg more than the previous clips.
I also agree with Eric about the swinging with the arms.
To engage the lower part of her body some more, try having her take a wider stance.