As far as I'm aware there's no way to change the way the gun is viewed while in your hands other than changing the FOV in general. You either have "cg_fov x" for general player FOV and "cg_fovscale x" for aim down sights FOV. No other options exist for the actual viewarms and you just have to accept that some of these animations were never meant to be viewed from that far back.
There is a third function specifically for gun placement called "cg_fovcompmax x" but it's only for BO1 and even then, broken weapon animations might still be visible.