NSC cleaned my FM2 viewfinder+focusing screen after I messed it up myself :sweatsm:
But I don't see any reason they would reject a FE2. IIRC Nikon (Worldwide) only supports the FM10 now, but Nikon SG still sells FM2 acessories (maybe they're compatible with FM10, I have no idea. Was never interested in the cosina made FM10).