After thinking of the strategies that could win, i came up with 3. the 2nd and 3rd ideas actually made me win the extravaganza!
A: The Ever Waiting Lineup
Make two people each stand on top of the prize givers to make sure no one can turn in fish. I prefer having a balance druid in Moonkin form or a person wearing a Ogre suit sitting on them, so they can't even select the legs. When people see you there, waiting for you to get off, they will tire out and eventually leave. And when you get there with your prize fish, tell your friends to jump an inch forward so you can turn in your fish from behind your friends backs!
B: Bloodsail Raiders
If you know a ton of bloodsail players, make them go on a raid with Booty Bay, and make sure at least one of them is using technique A. Everyone in the opposing factions will fuss up and start attacking the players. Then it's your chance to reel in your prizes.
C: Wait 'till The Next Week...
This is actually a Glitch. When I lost last week, I logged off holding the Alt button by accident. the next week, The 34 fish I caught were still in my Inventory, with the 1 day expire date still on them. In 5 minutes, we already had a winner!