The contest was so simple, how could anyone screw it up? The domain name must be registered to win. The obvious answer to how someone violate this simple rule is, well, simple.
The ‘contestants’ weren’t even trying.
The official entry vehicle for the contest was a public comments area that Adam controls (I use the term loosely, the casual observer would note that Adam controls barely anything). Some comments clearly weren’t contest entries, just people talking (typing, same diff).