This is just a guess. This might be signs of a backdoor plea deal. What I mean is that Andy was in the middle of it. If they need him to testify and rat out the rest of the jerks, the DOJ can write this letter with no visible sign of quid pro quo. Then Andy is free to spill his guts behind the scenes.
I'm not saying this is truth. I'm saying it fits with what we know. Someone was going to roll. Andy is a big enough fish to know how high this went, who all the players were, and who did what when.
