Lee,
You have taken a PMP boot camp two times before? I hope it is one that gives you a money-back guarantee. There are some that will pay for your subsequent attempts if you end up failing your exam. They're that confident you will pass it using their method. There shouldn't be much to prep for a crash course, unless they specifically tell you to do something. I would look maybe into another crash course, if you're still not passing with the one you've been using.