Except when Ukraine's territory as it is does not reflect the actual ethnic make up and history of the region. The causes of the Donbas war are the same as IRL. A mixture of government disillusionment and the fact that left-bank Ukraine (Eastern Ukraine) has significant populations that identify with Russia over Ukraine and the border 'crossed them'. So they want to separate and form Russian Republics or join with Russia since they view the land East of the Dnieper as historically Russian.
That's why this issue, like the IRL conflict, isn't an easy one to just solve at the negotiation table. Just like IRL there are stratas in Russia who believe they are liberating ethnic Russian's from a corrupt and oppressive Ukrainian government that has managed to occupy historical Russian land for nearly 30 years.
