it's less important who shot the plane
imagine Belgium and Netherlands having joint SAM practice shooting drones from a very high altitude, the authority which lets the civilian plane in that zone would be guilty if that plane is accidentally shot down and it's of less importance if the mistake was from Belgium or Netherlands military
"Ukraine intelligence sources said they had been made aware that several anti-aircraft systems had crossed from Russia into Ukraine at least a week before the MH17 incident. But they claimed the intelligence was not “100 per cent reliable” and could not have been used as grounds for “drastic moves” such as shutting airspace."
and this is utter BS, because ukraine intelligence sure knew at what altitude their planes got shot down, the only question is if they let the plane cross the dangerous zone with intention of accusing russian rebels of downing or it was just a classic soviet negligence, they are the first responsible in both cases