But what if it were true that the Russians paid the Taliban bounty money for killing U.S. and "Coalition" merceneary soldiers in Afghanistan? So fucking what?

In the very first place, by their mere presence in Afghanistan, these our mercenary soldiers, and those of our "Allies," are perpetrating a warcrime, for which they bloody well deserve to be shot. Which has been the basic, correct, position taken by the Taliban all along, I think, quite independently of any monetary reward that might have been offered. Because the extortionate, and illegitimate, national government of the country that I happen to be born in pays their wages, doesn't make them my troops: Kill them as you like.