It is logically impossible for all authority to be ordained by God except in the 'jungle law' sense: that might makes right. Of course an omnipotent God can only be logic itself (any other conception is incoherent), so this makes some sense. That's not really a reason to obey authority though: if you successfully evade or overthrow it then you are effectively a 'higher' authority, at the very least in the limited territory of your own person. Hey, those ordained authorities have to come from somewhere you know. They don't just magically drop from heaven.

"The third reason is, if we do what is right, the God ordained authority will commend you."

Certainly it worked for Paul. Though I suppose beheading can be seen as a kind of commendation from the perspective of a whacko suicide cult.