As much as I dislike all of the individuals you named I find it hard to believe they would approach Putin. Afghanistan was another failure of the UN, for years they sought a way with which to deal with the civil conflict and rise of the Taliban. For years they failed. There were many interests, factions and agendas afoot there. In any event, I suspect Iran or perhaps dissidents in the region, even certain elements who reside in Pakistan. And I further suspect that they called on Russia for arms and money, not overt support. This could well be the reason Putin said we would be sorry for going to Iraq, he knows that in the aftermath of victory comes the extremists and ongoing, bleeding unrest.
And he was approached through several channels, which means a more sophisticated group than Pakistani dissidents, who might be able to contact an embassy, but would not have the ability to go through multiple channels.
And Bush didn't comment on it at all. He just let it hang there. I thought that was very interesting.