Interesting. I've wondered why in past situations America and others have been very aggressive in gaining access to crash sites but in this case they have not.
Earlier when this incident was yet fresh there were reports that Ukraine had sought to down Putin's plane, which looked very similar to the Malaysian plane, but had mistakenly shot the Malaysian plane. Perhaps there was some merit to those reports which quickly got pushed aside.
One of the evils of war is the severity of accidents and mistakes that occur and how such are often twisted into propaganda efforts against one or both sides. Caught in the middle, besides those who suffer directly, are the families which are lied to, kept in the dark, misused and put through much more grief upon grief.
Eventually, perhaps the truth may be known, whatever the truth of this is.