I go with Option 1. It must be seen as lawful, as the self-declared independence of the two Donbas republics must also be seen as lawful, IF we are to regard the secession and self-declared independence of Kosovo as lawful.
If at any time the West shall reverse itself and say that what Kosovo did was unlawful, then a CONSISTENT legal case could then be made that the DPR and LPR also acted unlawfully, and I will review my position.
But as long as we accept the legal precepts that the West has lavished on Kosovo independence, then that same cloak of legality MUST be extended to the Donbas, and thus all that flowed from that initial act - including the SMO - was indeed done according to international law.