My "Conspiracist Thinking Detector is softly tingling right now, in a way that makes me sort of narrow my eyes and tilt my head to the side, like this:

The funny thing about Snowden is that, when he releases some kind of leak or claim, most of the time there seems to be no readily available way to either find confirmation from independent sources, and likewise it is really difficult to falsify these claims.
In other words there are no guarantees, at all, that he isn't just making **** up.
Yet everyone seems to just assume that all the things he releases are actually genuine documents from the info cache he took with him.
The only "confirmation" that he possesses some classified information is the response from the US. Clearly, he had access to a lot of information, took a bunch of it, and escaped the country with it.
How much of his releases are
actually from this legitimate cache of documents is anyone's guess. Any particular document could just as well be real or a forgery for all that I know, and I have no means to validate or falsify any of that ****.
What I'm saying is - it's pretty dangerous to just assume anything released by Snowden and his associates - or even just claimed to come from Snowden - is actually legitimate. Much of the official documents are probably genuine (and profoundly uninteresting even if they are classified). Determining if a particular released document is genuine is a practical impossibility.
This particular document seems to be a new employer orientation presentation with generic graphics and slogans with some "SECRET//SI//REL TO USA, FVEY" stamped on top and bottom of every slide.
Literally anyone with a modicum of ability with the challenging software known as "Microsoft Office Powerpoint" could put together something just as convincing, as long as it's general enough to not be feasible to disprove, you claim it comes from a source that makes it practically impossible to validate, and make sure it has enough content that appeals to Conspiracist Thinking. Someone with access to real documents could even make them indistinguishable from a real document by making all the official-looking "classified" -markings, logos etc. identical to what an official document of that particular classification level would have.
Is it real? It could be. Or it might not. There is absolutely no way to know, and trying to use the "Snowden says it's real" as an actual argument is not.
Also, if they are supposedly good at posting false info, how can we thrust stuff that Snowden says? Maybe it's all a coverup of something much bigger? Note, they could have discredited him if they wanted, so they obviously don't, for whatever reason...
If it's real, they don't discredit it because Streisand Effect.
If it's false, they don't discredit it because every time you try to discredit a conspiracy theory you end up just strengthening it.
E: bad formatting at the beginning