My late Brother Jim spied on the Cinese for the NSA. He taught me that most intelligence is not a video recording of a specific act. It is usually a lot of little things that assemble to make a big deal. The movie "Zero Dark Thirty" shows this in a dramatized way. They traced bin Laden indirectly, piecing together information developed watching the acts of others. During the process they looked at a lot of information that did not support the ultimate outcome. Information in that setting is rated by its reliability. Very reliable information results in a high degree of confidence in the direction it leads. The chances of 100% confidence, without that video I mentioned, are extremely remote.
The question we should ask is "Why would Putin do this?" The puzzle pieces are there suggesting that he did. Establishing a strong motive would increase the confidence one would have in the information. One idea is that he knew this information would get out into the publiic domain and further disrupt the domestic tranquility of the US. That does benefit his cause. But, this is an expensive operation, and it might lead to sanctions, which would disrupt Russia's economy. Revenge over our actions against USSR's invasion of Afghanistan, is one potential motive that has surfaced. Again, this is too expensive for that to be the goal.
The USSR invaded Afghanistan in order to build pipelines to the Port of Gwandar, to make it easier and cheaper to compete in the lucrative energy market in China and India. With the development of oil fields in the Arctic and those markets becomming greater, this goal would still be operative. By paying the Afghans for doing something they were already predisposed to do, Putin develops friendships that would help him get his pipelines, and keep them safe. He has paid a lot of money to disrupt similar pipelines in the US, aimed at supplying the same market. All of this would make the story currently being circulated have a high percentage of confidence.