Why is it in Russia's interest to stop them? These groups have an arrangement that as long as they don't attack Russia's allies they are untouchable. They bring in money and build up real-world skills that Russia is eager to have. Its like the old-fashioned pirates, as long as there is plausible deniability and they only harm the competition they are a great asset.

So yes Russia might be blamed as they consciously choose to let these guys do their thing. China and NK do the same, as do US, UK and Israel with similar stuff on the other side, done by NSA, CiA, etc