Bob, I totally understand you and Dr. Dave being very skeptical of the shot. It truly is an amazing shot. One that none of us thought was possible, and many still don't think is possible after seeing it.
While very true that Cleary did NOT meet all the requirements of the instructions, I believe the intent of the instructions was to prevent someone cheating on it. Cleary's video clearly shows the ball bending far more than what the meaurement actually stated. As the ob was clearly well past the doughnut measured from.
You and Dr. Dave have done MUCH for the pool world. Since you were willing to pay for a fully legit video (meaning followed all the rules to the letter), and Cleary's video clearly shows that the ball can be bent quite a ways, and no one else has even come close to bending it as much as he has, I think it would be in your best interest to declare him the winner (at least so far, as it isn't over yet) and then get with him to try and duplicate it so there can be some understanding of how it was done. (talk about a run on sentence!) I don't believe it is worth your reputations to hem and haw about his video and not pay on it. And, being a stickler on the the exact wording of the rules after viewing the video would only be viewed as nitpicky and never wanting to pay to start with. I don't believe that is the position either of you want to be in.
Now that we all have seen it can be done, get with him to keep attempting it and see if you can figure out what just happened.