Bullcrap. The Kiev coup government attacked the Donbass for the crime of opting out of the coup. Kiev decided that seizing the Capitol and their legislature at gunpoint means that everyone in the borders of old Ukraine had to stand up and salute.
When you throw a coup, you do not inherit everything the old country had. Because you took power by force, you only inherit what you can control by force. Everyone else has the same rights as those Banderists that did the coup.
The government in Kyiv was and is legitimate. If Yanukovych had been overthrown by a coup, as you characterize it, the proper response would be to call new elections, not to secede. National elections were held, twice. Donbas could have fully participated if not for Russian occupation. With those two elections, any justification for Donbas secession disappears. Nor does it justify Russian intervention.
By the way, your use of “Kiev” rather than “Kyiv” shows yourself as nothing but a Russian apologist.