Thanos Thanos:
Russia's always been pretty successful at dodging responsibility for atrocities, like the Katyn massacres (that they're still insisting the Third Reich did) or the mass murders they committed in Afghanistan. They'll dodge this one the same way. The self-serving games played by the large powers, even one as physically decrepit & as intellectually/morally diseased as today's Russia, never really change.
No, not much will change. I think it's important that we have a proper investigation though. It'll mean nothing to Russia, but a documentation of the crimes by an investigative body will help deflect the propaganda efforts to deny, deflect, obfuscate by Russia and its useful idiots.