[Oculus Rift] AvatarSurfaceShaderSelfOcluding.shader will not import

Hi guys, new to Unity here. My friend and I were building a project in Unity 5.6, everything was going fine but after a recent Oculus SDK update we found that the AvatarSurfaceShaderSelfOcluding.shader was no longer working. Anytime it was called, it would say file not found even though it was placed in the right directory. This shader is responsible for the colouring and shading of the hands in the experience, and currently don't exist. I was wondering if anyone else has run into this issue, and what could possibly solve it?

 

Update: We have re-imported the shader, but it now says "shader is not supported by GPU". Are there any workarounds for this? I know that the GPU cannot be the issue since it supports DX11 and have run it before on that GPU.

 

Guys this throws the same error in V1.18 which I just downloaded.

 

I'm coming across this issue with the script not being able to find the shader as well. Not sure why.