I don't know. A Starfleet officer (who just happens to be the son of a highly-influential Vulcan ambassador) effectively stages a one-man mutiny, steals the Enterprise to go to the most forbidden planet in the galaxy, and turns over a disabled Starfleet hero to the largely unknown alien inhabitants of that same forbidden world, all in defiance of the death penalty.
I can see Starfleet wanting to keep that whole affair under wraps. Sounds like "Need to know" type material to me, not something you'd want in the public record. Better to stick it in the same top-secret file that covered the events of "The Cage."
But the inhabitants, and their motivations, weren't unknown after the original story had been shown and presumably taken at face value lest the decision that Mendez communicated wouldn't have been arrived at. As for Spock's actions putting Starfleet in the position of having to make this kind of determination, if you're implying that clearing him of his multiple wrongdoings would be judged by many in Starfleet as being biased due to his parentage, well I won't underestimate the political calculations or suspicions that might have been engendered by his exoneration. I might offer that a reasonable conclusion one could draw in looking at the whole picture, if it were made available to do so, was that Spock determined and followed through on his course of action, not because of some abstract sense of fairness or compassion, but because he had been on Talos IV at the time of the original incident, knew what had gone on there, and was a longtime officer under Pike and was fiercely loyal to him. Perhaps your sense that in the process of taking it upon himself to do what he did, regardless of any extraordinary mitigating rationale, even one ultimately sanctioned by Starfleet, the example Spock set would inevitably lead others to determine a just cause that would warrant the disobeyal of explicit orders or commonly understood directives. That's possible, even though I don't believe we can cite many instances that such behavior actually took place i.e. Tracey, Garth, Decker? Also, I would offer that at no time in the future is the reckoning of Spock as one of the finest officers in the fleet, and not just by the Enterprise crew, appear to be compromised.