Metal Gear Solid: Peace Walker

[Onykan]

Hello everyone, I am new to this site.
As a lot of people, I cannot win during peace walker 2nd fight.

I am using the 0.9.1 version of ppsspp and my problem is that I am playing with the EU version of peace walker.

The cheat code (to kill it with one shot) doesn't seem to work, so I need to know if there is another for this version of the game.
I also try to play with the 0.7.6-15 version of ppsspp but my saves are not available

Let me know if you have a solution for that and thanks in advance in anycase.