I didn't know there was more than one.
This one is based on a csr2 model so that fix won't work. The meshes of every mirror need to be detached for mirrors.ini to work as it uses the left, right and central mesh names and this mod has all of them in one mesh.
You need to detach those three, map them as the pipeline says on page 38 and then put the mesh names in mirrors.ini. Csp mirrors don't need al that.
As you can see the mirrors on this one are all in one, while cars that use mirrors.ini like the kunos giulia has all of them detached as single meshes
I know you're not the one who requested this explanation so sorry for quoting your post and then adding all this.