To add to your point, in Italy and other Mediterranean economies accustomed to using oil from Libya, Russian oil (and Russian controlled oil from Libya) can easily displace Libyan oil from other vendors. It is worth recalling that Putin’s dissertation for his law degree when the Soviet Union collapsed advocated in detail how the new Russian state should use control over oil resources to rebuild its lost strength and power.
If memory serves, LIbyan oil is some mighty fine crude, and extraction costs are lower than the post-Soviet fields, many of which are in decline. Regarding your earlier idea, that fits well with the idea of the Russians getting at the very least a cut of the Libyan oil money.