Well we won't really know for sure, but I think there was more to it than simply that George wanted to buy guns with the winnings, and the other 2 wanted to put kids through school, etc etc. I mean, they all must have talked about that stuff already. That video taped conversation you heard on that, was canned (I suspect...which doesn't make it not true. but they probaly coached them on how to say what they wanted to convey...IMO).
I also suspect that George figured he couldn't win against Brian Zins in the final competition (yes that's what I think), and also he and Chris had been friends (that part I believe), and he wanted Chris to win over Brian. When George saw that Chris was choking in the pre-final elimination rounds, he had to make a decision...either him or Chris up against Brian. I think he made the right choice. If he had chosen himself, Brian Zins would have won, and I think he knew that.
Either way, I think Chris deserves his victory to the the fullest. Because being topshot, isn't just about shooting weapons. It's also about sportsmanship, and sportsmanship includes "team playership" if you will, and the fact that Chris and George made friends, which helped Chris win in the final rounds, well...there is nothing unfair or illegal about that.
Now it would be illegal if (let's say), Chris paid off George later. But I'm pretty certain the TOP SHOT Lawyers made sure and had these guys sign documents which would void their winnings if they were caught doing something like that. So the odds of there being any collusion is pretty much 'NIL.