Hang on to the rope....... Or crash hard enough to blow out of the bindings and fly towards shore. Kill two birds with one stone.
JUST KIDDING! Some lakes have a LONG swim unless you want the really long walk of shame barefoot! I am guessing if you get the issue of removing your feet from the bindings faster, the swim part won't be as stressful. Also, remember, you only really need to get yourself clear of the course and skier path so don't fret too much about it. Secondly, if the tournament is so stressed they can't wait a few seconds for you or provide a little help on the shore...... or maybe ask the tournament official. Or atleast let them know you struggle with those two things currently. There should be a little help and understanding.
As a Dad, I worry about my 6 year old in this regard. This past weekend, he fell for the first time in a tournament. I happen to be driving the boat, and my wife and daughter were not with us. So he had the long swim at Warman in Vancouver. I was surprised by the time I finished his pass at 23 MPH and returned at 36 MPH he was almost up on shore.