Russia is not interested in split Ukraine. It does not need a fringe lawless state with conflicting ragtag bands, as it was in 1918. What Russia needs is an independent neutral (with possibly a slight bias towards Russia) stable Ukraine, which can act as a trading partner and a buffer zone with regard to cancerous NATO expansion.
Russia want the eastern provinces of Ukraine to join the Eurasian customs union (which includes Belarus and Kazakhstan in addition to Russia). I don't think that Kiev will agree to that demand.