capps,
Good questions, but questions for which I don't have good answers -- only theories based on what little I actually know.
As you likely know, my theory is there were very young kids involved in this crime, and I think the 13-month GJ investigation uncovered who at least two of them were. But there may have been a third underaged male (under 10 years old and thus not able to be prosecuted) also involved; and there also may have been a young adult somehow involved, but perhaps not directly involved in the murder.
Therefore, IMO the Ramsey coverup is likely shielding at least one Ramsey family member, and perhaps one or two non-Ramseys.
It appears Fleet White wanted the Ramseys to spill the beans right from the start -- but the Ramseys chose the coverup route instead, thus casting a shadow of suspicion on everyone even remotely involved -- including the Whites.
IMO Fleet White knows who the likely killer is because he knows first-hand that John has lied and is involved in a coverup. Fleet has probably already passed this info along to LE, so he can't be charged with obstruction. But I think Fleet White would like the whole truth to come out, including the names of the children, so his family's name can be cleared.
In fact, everyone in this case who's been thrown under the bus would also appreciate the truth to be known. IMO the ball is in the Ramsey's court to voluntarily disclose the truth and put this case to bed. There would be no prosecutions, just empathy and thank you's.
BlueCrab