Secondary fire not springing back

[SineMetu]

As stated in the title, during a playsession as I pulled the secondary fire trigger, I heared a spring noise and the trigger wouldn't return to it's original position. The input still registers so the electronics shouldn't be damaged.
I've opened up the joystick but the part itself is buried beneath a couple of layers of boards. I believe the issue can be easily sorted by reattaching the spring, but does anyone know how to get to the trigger itself?

Thank you in advance.

Joystick is the MCG Ultimate w/twist.

[skarekrow]

Here is a video for replacing the folding trigger on the MCG Pro, maybe it will help with proper disassembly and reassembly for your ultimate.
https://www.youtube.com/watch?v=u8jEKe6l_GQ

Cheers !