Gentlemen, why not to talk technical issues (or issues that may be related to facts) rather than emotions and politics?
I am not sure the recorders will help if it were a ground-to-air missile. Studying the debris may only help if it were not the "Buk" system involed, but a larger one like C-200/300. The locations of the latter ones are known well enough and this could narrow the scope. But the Buks are owned by all the sides currently blaming each other.
A couple of days ago the US officials vaguely mentioned they had some proofs that the launch was triggered from the territory controlled by the separatists (village or town of Snezhnoye). Could all this stuff be put on the table? If they refer to the early warning satellite system (which indeed works 24/7), its accuracy is in (big) question. I assume that the 90-95% probability ellipsoid is measured out in tens of miles and thus could also cover the locations of some Buk launch systems of the regular army.
The Russian MoD reported shortly after the accident that their stations of radio-intelligence recorded the Buk radar signals operating in different combat modes, the signals coming from several Buk complexes arranged in a networks. They were, for sure, the army ones (because only army has the networks of them). It is also known that they were relocated to the conflict area shortly before the tragedy. Actually means nothing, only proving that the teams were either training or testing the systems.
If there were some LEO satellite photos ("spy sats") that pictured the launch, this would raise another question: how could it happen that the camera was looking at this particular location at this particular moment? The constellation of those sats is not covering the whole earth area on the 24/7 basis, at all. They are orbiting the planet, not hanging on a geostationary orbit or a highly-elliptical one.
Thus, I am afraid that totally convincing "technical" proofs would not be found.