To the seemingly firm point that the alloys will offer few or no elemental surprises,

If such stuff is being stored it may just be for that purpose, storage.

Then again, maybe this statement is disinformation, meant to give cause to be wary of the whole story.

Me, I don't care much either way. I believe we're not alone, very likely have been visited, that some evidence is real, but I will probably only get excited if ET actually shows up in a way that is ultra public.