Those executive orders are irrelevant now that Bush is no longer a president. And any executive order covering up a crime is criminal in itself. Obama's administration has a constitutional responsibility to prosecute war crimes. Of course, not that I expect them to do so. It is politically just not convenient and no doubt Obama is just hoping that the whole issue will just go away and American people will forget about it.
I read something, and have not had time to find it that strongly suggested that he had put a pretty good lock on all "executive powers" issues. In other words, if they were acting ON HIS BEHALF, it got them a free ride in US courts. Not so much by international law. I am going by memory since it was in 2006 but I remember it to be a big enough irritant that it would not be playable [especially with so much else to do now].
And maybe that is all just as well. It might not be right but at some point we have to deal with the problems of NOW and rebuild our reputation in the world. Fortunately or unfortunately everyone in the world that matters understands the politics of the matter.