The reason that Crimea, Donetsk and Luhansk did not participate in the elections is because of Russian occupation.
If Russia had lived up to its obligation to recognize Ukrainian sovereignty and had not twice invaded, there would be no war. This war purely the result of Putin’s decision.
For EIGHT YEARS the people in Donetsk and Lugansk, especially ethnic Russians, had been persecuted and killed by the Ukrainian nationalist regime that took over.
Those in Crimea had sought independence from Ukraine since the fall of the Soviet Union.
You are completely ignorant of the region.