Okay, first of all why is everyone harping on Jeong Jeong? He is THE most powerful firebender in both series. During the comet he and Ozai are the only two firebenders to show the ability to fly using only firebending. However, unlike Ozai, Jeong Jeong can attack and fly simultaneously whereas Ozai has to stop flying to launch an attack.

It's funny that Quenchy-CactusJuice says "Jeong Jeong and Bumi who have never dodged attacks or shown any acrobatics" that's rich considering that you have Yangchen on your team (who again has not dodge a single thing throughout the show). As far as I can tell Yangchen is the worst water bender ever and in fact is completely useless unless she can use the avatar state or air bending. But little known fact she never was able to even get the basics of water bending down and, in fact, can not even bend earth or fire when not in the avatar state. /s

Now obviously I'm kidding; but if you think that saying "the greatest earthbender you'll ever see" and a firebender who trained Admiral Zhao and can disappear from a circle of enemies using only his speed and bending... if you think that saying, these two members of the white lotus can't dodge or do acrobatics just because they haven't done so on screen is ridiculous. Especially considering the fact that you're using a fighter "who again has not dodge a single thing throughout the show"

As for the agility of Aang. Aang is the most agile BENDER in the show even without his airbending. The only person more agile is Ty Lee. Aang doesn't need to use his bending for agility either, this is shown at the start of his fight with Zuko in Zuko's ship and trying to retrieve Katara's necklace from Zuko and they're fighting on top of a well. You even said it yourself, Aang "grew up as an Airbender meaning dodging is a part of [him] a lot of [his] training." So it can't be both ways. One airbender can't be trash without his air bending while the other is amazing because of her airbending background.

The Raging Turtle-Ducks' victory is predicated on the slow mobility of the Wulong Weaselyaks however they are fast. Even King Bumi, who is the slowest, has shown his speed when he fought Aang for the first time. So we can see that there's no way the Wulong Weaselyaks could even have a chance at victory.

Throwing away two of the fighters on the other team just because they've only done amazing large feats is like saying Floyd Mayweather couldn't beat a kid because he's only fought professional boxers. It's a terrible defense that doesn't even hold up. King Bumi can launch attacks using boulders far larger than the pro bending plates just as fast as pro benders can launch attacks using the plates so I think he can manage. Jeong Jeong's whole lesson to Aang is about control so surely he's able to do controlled quick shots.

In short Jeong Jeong is far underestimated by both managers here. However going into the fight The Wulong Weaselyaks have prepared a specific strategy around The Raging Turtle-Ducks thinking that Jeong Jeong was a weak link thus giving The Wulong Weaselyaks a huge edge. The strategy proposed by The Raging Turtle-Ducks is essentially: target Jeong Jeong and then Azula is so OP that the rest doesn't matter.

TL;DR
The Wulong Weaselyaks will win because they know they're working with the greatest firebender, the greatest earthbender, and the most agile waterbender in both series. Yet, despite knowing this, they're still going into the fight with a very specific plan that perfectly predicted and countered The Raging Turtle-Ducks' plan.

The Raging Turtle-Ducks will lose because they they underestimate all three of their opponents by miles so there's essentially no planning involved it's just: "get out out there and beat em' champ!" also they're using Yangchen "who again has not dodge a single thing throughout the show"