I don't have access to my copy of the SERTS data from where I am right now, and it looks like the SERTS link is now offline, so I can't post the link at the moment. I will upload my copy of the SERTS data and post it later today or tomorrow. In there you'll find all sorts of highly ionized neon ions emitting most of the light, and little or no light from the lower ionization states, so that concept simply doesn't fly.
So recall, MM, that any 3.5 meters' worth of He I, He II, Ne I, Ne II< or Ne III will attenuate 17nm VUV. So will any 0.5m column of any metal whatsoever in the neutral or first few ionized states.
So you are claiming that in the 3000+ km layer between us and your "metal surface", there cannot possibly be even 0.01% of neutral material, nor single- or double-ions of any sort?