Assault Joint

As soon as Asuka leaves, about ten Mafia goons will show up and start attacking you.

Another Set Up?

You'll need to dispose of the Mafia who are coming after you with shotguns and machine guns. A few well placed grenades do a decent job, but you can't beat the shotgun or flamethrower for multiple kills.

Once they're all dead, you'll need to head to the compound to the North of the island where you'll meet Asuka's guys. They'll tell you to get into position and they'll attack the front entrance. Run into the middle of enemies and they'll start attacking you, meanwhile Asuka's guys will run away.

Kill all of the guys who are attacking you, then make your way into the compound, jumping over the gate by pressing A+B.

Once inside, King Courtney will want to fight you, although he'll do that with the help of about 15 of his guards. This battle is much easier with a flamethrower than any other weapon as you can just keep running back and forth burning the hell out of everyone.

Once you manage to kill all of his guards, and damage him enough, he'll order more of them onto you. The same thing applies. He'll then order even more to attack you.

Finally, after killing all of his goons, it'll be time for the final battle. He'll have an RPG and won't be afraid to use it, but if you're using a flamethrower you can just keep flaming him and you can take off all of his health without even getting touched.

King Courtney will tell you it's over between you and you're the winner.

Mission Passed!