I pretty much agree with your assessment. But there is one additional wildcard to consider in all this: Trump has cronies and campaign supporters entrenched in the FHFA decisions with huge investment rewards pending the fate of F&F. As a Machiavellian type, Trump could deliberately choose someone to be the fall guy who gets blamed for upending the GSE reprivatization in a way that costs the fundies $ billions. Remember when he fired and threw Omarosa under the bus and then said he knew nothing about it?
Calabria's historical views/opinions on FnF are well known. If Trump chooses him I believe it is because he will have assurances from Calabria that they are on the same team and Calabria will be a team player.
I agree, but if Trump really didn't want FnF considerably restrained, why pick Calabria? There are plenty of other candidates that have been far less outspoken in their criticism of FnF.
To me, a more plausible explanation is that Trump's views have actually shifted to align with Calabria's and not vice versa. Nominating Calabria will be a big tell from the administration, and not a good one for us shareholders.