Nope. Treasury paid $187B in cash to FnF and got $310B back. That's not even two-fold.
Their actions disagree with your theory.
Takings cases over the NWS were already brought and all of them are either dead or nearly so. Good luck trying to get a takings case over a senior-to-common conversion (which helps the companies!) to stick.
(from another post)
A senior-to-common conversion is not a wipeout or cancellation of the existing commons. It's just a huge amount of dilution, the same as what happened with AIG.