Moscow is probably lying. I say this because governments everywhere lie all the time. Ukraine lies. NATO lies. DC lies. For example, Bush II told us that Saddam had huge stockpiles of destructive weapons. Except that he didn’t. You get my point.
We might get the truth about a major event 20 years after its occurrence. But probably not.
Saddam Hussein did not need hundreds of tons of anthrax powder; fifty or a hundred pounds would be a lifetime supply for a guy like that and he DID have that much of the stuff. The anthrax used in the attack that followed 9/11 had Hussein’s fingerprints all over it. GW Bush did not lie us into a war.