Most transparent administration ever?
They probably are. You can't count any administrations prior to the Freedom of Information Act- ALL of them were more secretive. That leaves us Reagan, Bush I, Clinton, Bush II, and Obama. All of these were accused by their enemies of not being transparent enough. All of them had congressional investigations, and in each case Congress complained that getting info was like pulling teeth.
We've seen this game played over and over. Nothing is ever proven, there is never a smoking gun, it's a circus that gets in the way of governance. Only the partisans that hate the President whoever he is seem to love this stuff; the rest of us are bored out of our minds and wish it would just go away. So ####### tiresome.