Russia will destroy the evidence. USA has already confirmed that it was a Russian missile, but only USA has the satellite network capable for that kind of intelligence.
This could be re-confirmed by international experts examining the evidence on the ground and that is why Putin is destroying it.
I have a theory on why. When it comes to sanctions from the EU then there will be some political forces that work against it. For example German hippie-stalinist parties will work on people claiming that the USA is lying and there is no need for sanctions. They would get a lot less ears listening if the evidence could have been confirmed by respected German experts on the crash site.
Where did you get the notion that only the USA has satellite capability over eastern Ukraine?