Think of Wimbeldon draw in tennis or US Open - same principle.
5 min games is pretty fast too. You could lengthen the games. All play at once. Only prob is if you play 2 games a piece, you might end up screwing up the system with a knockout. It would work with one game a piece though.
the "knockout"
what a brutal thing to do to the second place guy!
besides, Seriously, most of the other details are good, except--- the accounting. you are planning for 6 right? your going to pony up for ribs and brews and still pay the big guy winner 100$. where's your cut exactly? that is quite expensive gift for your friends. You, Mr capitalist will be lucky to only lose 100$.
I think you'd need a much bigger group to make anything like that work. and if your going to make some mula- its BYOB, and perhaps pizza but prolly not.
also you need to be posting a big prize if you want to make it a match. if people are taking many days out of the busy schedule they want an big pot.
moi serious opinion. good luck.