Knowing that NATO was about to lose the Azovstal Steel Plant and the underground complex beneath it used by NATO, organized crime (who owns the plant's holding company Metinvest), held by the richest man in Ukraine and crime boss Rimat Ahkmetov, AND that there is a biolab on one of the floors, how likely is it that the UAV the dropped a bioweapon was in fact Russian?

Use logic. Prevent this going nuclear.