The conspiracy theorist in me says that the negotiations broke down at more than one man from Gitmo released for this traitor - but then VA, CIA flub hit and Obama gave away five guys to have something to carry him for a week and make VA, etc. go away.
Obama needed a headline to mute the VA problem, so after a three year dance with the Taliban, he agreed to release all five bad guys so fast that he neglected to notify Congress per law. He can neglect Congress as he is Emperor/Dear Leader and the GOP is toothless.