Reading that passage from the novelization, I wonder if this is where so many fans got the erroneous idea that Kirk was somehow exceeding his authority by putting Khan and his people on Ceti Alpha V, or that he was doing it without Starfleet's knowledge. This is clearly not the case, as the episode itself shows Khan and McGivers' hearing as an official proceeding, with dress uniforms and Uhura making an official recording.^^ And this is where I call bs on the rationalization. In “Space Seed” Kirk held an official hearing that would have become part of the official record. As such he did not hide his decision and action from Starfleet.
But back in 1982, most folks only saw "Space Seed" when it happened to pop up in the syndication rotation, while VM's novelization would be sitting on the shelf, always ready to be reread over and over... Thinking of it that way, it makes sense that the idea of "no official records" took root with fandom.
Yes, that's perfectly plausible to me. If the story about Khan came out, it would not make Starfleet look good in the public eye. I'd much rather attribute Khan being forgotten about to either Starfleet bureaucracy (incompetence) or a more malicious reason like paranoia than impugn Kirk's character by saying he broke the rules when he clearly did no such thing.It makes sense to me that Kirk did make an official record of the proceedings and that Starfleet then highly classified it. They might not want it on the public record that a decorated Starfleet officer had unfrozen a bunch of 20th century Augments who'd managed to seize control of a Constitution-class vessel.