i'm going to say this one last time: julian assange has been living in an embassy for nearly five years, with essentially no unmonitored contact outside of it. i don't know whether he believes what he says or not. but, i don't think his analysis is very valuable.
what i suspect is that the cia played him as a patsy, and that he probably seriously thinks he had contact with a real whistleblower. let's take that step back and do the thought experiment...
if the cia (or the fsb, even) were going to feed information to assange, how would they do it? would they present themselves as cia (or fsb)? there are certain scenarios where either of them would impersonate the other, but not in this circumstance. if the cia (or fsb....) wanted to feed assange information, they would present it to him as coming from a disgruntled whistleblower. that is consequently what assange would think.
the point is not that assange is lying. the point is that nobody would ever tell him what's happening, and that the chances that he has any idea what's going on are consequently extremely remote.
there is of course also the possibility that he's come to love big brother, after all - no doubt as a consequence of some suggestive prodding. i find his choice of interviewer a little concerning.
but, he doesn't know who fed him the files or what they were trying to accomplish. and, you should not be tricked into thinking that he does.