“Russians have the site, and have been busy removing and destroying evidence.”
Seems to me there is very little evidence to destroy. We already know what took the plane down, Nothing on the site is going to tell us anything about that...
As for who pushed the button, It’s certainly not going to tell us that.
Well, for starters, one could determine whether it was an air-to-air missile versus ground-to-air. Which, in turn would make the Russians shut up about some of their conspiracy theories.