So you want to throw rules at the problem and hope it disappears? You'll end up with fewer valid results as everyone will break a rule here or there or be accused of cheating.

I would rather see LOTS of tiny live or online events with prizes lower than $1000 and with stipulations against consecutive prizes. Have dozens of competitions per region and then have a global live competition every year or every other year with the top benchers from this series according to a points system. More competitions mean more chances to win. More competitions also eliminate personal time constraints. So what if you miss one or two out of 20 competitions, you have plenty of other chances to compete.

Regarding score validation I'd rather see a software system that would validate basically time stamp and validate the system. Video is tedious to record, edit, upload, and view. Perhaps a program that performs a screenshot, encodes it into a payload along with a time stamp, system information pull, a IP based geo-lookup, and then uploads the result to a central server?