IIRC, Rather's initial report claimed the documents had been "authenticated". He knew the documents they had were photocopies, which means authentication is intrinsically impossible: the paper cannot be tested for authenticity; the ink can't be tested for authenticity; the letters can't be examined to be sure a typewriter (= ribbon rather than a printing press, inkjet, or laser printer) was used. Just off the top of my head. Rather could not have been so stupid as not to know he lied when he said that.
Of course, being a photocopy (of a photocopy, of a photocopy, of a photocopy, ...of a photocopy, of a photocopy, ...) was the least of the problems with that fauxny "memo".
CNN is playing this close to the vest, and, predictably, the rest of the MSM aren't interested in how it played out, since Trump "benefited". My wild-ass speculation:
* CNN's people ran with a sole- and annoymorous-sourced story, bypassing some processes because it was such a hot "gotcha";
* The Trump supporter and/or the Russian investment group quietly called CNN and pointed out one or more key easily provable falsehoods;
* The Trump supporter threatened to sue, based on those easily proved falsehoods;
* CNN backed down, throwing up an editorial processes and standards smokescreen for public consumption.
IMO, there is no way in Hades CNN would have withdrawn this story and apologized to one of its prime targets except under threat of a very expensive and embarrassing (Can you say, "Discovery"?) lawsuit. CNN, like the rest of the MSM, are too arrogant and self-righteous.
