There's a pretty clear message here that the US isn't fucking around.
Darkside has opened negotiations in the tens of millions in the past [0], with an average demand in the millions [1]
[0] https://krebsonsecurity.com/2021/05/a-closer-look-at-the-dar...
[1] https://www.areteir.com/darkside-ransomware-caviar-taste-on-...
I wouldn't be surprised if the US Government here reached out to foreign governments for assistance in dismantling their infrastructure (it almost certainly was not on US soil).
An individual hospital probably couldn't garner that kind of backing, but oil pipelines? The US would probably be willing to use military strikes to keep the oil flowing. A small country would be very willing to help out to maintain good will.
(This isn't some anti-Russian screed or anything; this is just one particular point where the Russian government is IMO behaving improperly. I could elaborate if needed.)
Presumably in return for some sort of gratuity. Perhaps they decided they weren’t getting a big enough cut.