I'm wondering where they found a big enough hanger to hide this plane. I'm betting on a triad of North Korea, Pakistan, and Iran as the ones behind this obduction.
I believe US intelligence and the NRO in particular know exactly where the plant went in but the information is highly classified due to its acquisition source and simply won't be released. The only time info like that might be released is if there potentially are lives to be saved but there are none.