Problem with motor6d/bone viewmodel mix

I followed a tutorial to make a fps view model. It turned out alright, but I wanted to make it more realistic so I used a skinned mesh for the arms, and I can’t really figure it out. This is my first time really handling skinned meshes so I don’t really know much about them. The gun is still welded with motor6Ds, but the arms use bones. Im now running into 2 problems:

  1. I can only animate the bones in the animator. Im testing if it’s rigged properly before exporting it to blender, and the motor6Ds holding together the gun seem to be non-existent.

  1. The gun won’t move with the hand. This might have to do with the first problem, but I searched it up and it seemed like many people were having the same problem. It makes sense that you can’t weld the handle of the gun to any bones, but I can’t find a solution. The only solution I found that seemed like it would work was exporting the gun to blender and adding a bone to the gun…

so, any help?