So if you call your admissions officer, they will tell you? But the BGO is not allowed to tell you?
I believe (and, as a USNA grad, I hate to use that word
) the reason that the RDs can give out the info and BGOs can't is that the data is the BGO's system is unofficial and can change.
I have on occasion, seen the status of candidates change, both for the better and worse. As an example, on Nov. 1, the BGO system may indicate that Candidate A is scholastically qualified. On Jan. 1, that qualification may disappear and go back to "not evaluated." I've also had candidates who were initially rejected later become qualified. I believe the above happens as USNA reviews more and more packages and thus has a better idea of what the overall qualifications of the class are/will be. This may cause some reevaluation, especially of those candidates reviewed early on.
You can imagine how devastating it would be for candidates to get preliminary/bad/wrong information either way. Thus, because Admissions is the keeper of the official decisions, they are the ones who are authorized to discuss those decisions.
Again, the above is only my best guess but it does explain things.
Also, I think most BGOs who violate policy are doing so in a desire to help out their candidates. Good motivation but potentially disasterous results.
Sorta like warming up in the bullpen. 
