Sounds more like a Steam Overlay issue than a DXVK issue to be honest. Even if it doesn't hook D3D11, it should at least enable its Vulkan layer.
In any case, there's not much I can do here and since Windows isn't the intended platform, I don't intend to spend time on the issue.
Nothing extracted yet.
When using DXVK (and D9VK), Steam Overlay will not hook to any game using the wrapper.
System information