Try loosening your grip and following through on the same side of your body - not across, right side if you are right handed, shorter swing and follow through helped me
The instructors should get credit for putting up with what looks like a very awkward shoot. It looks and sounds like it was very windy. Plus the sun was low and it looks like that court was built in an unfortunate position in relation to the sun. Hope they got paid good $$$ at least.