Problem with ThrowN bone

[Brawling Moi]

Hello, I'm having a problem with the bone ThrowN (Captain Falcon). That bone causes a part of the geometry to mess up, just like in the image.

I tried to fix it by decreasing the Weight in ''Set Weight'' on the Weight Tool to 0,0; but it keeps like previously (well, a part of the geometry is fixed, but not all)

So if there's a method to make that bone to not have ANY influence with that part of the model, please let me know, Thanks.