Ok, in an effort to use the story companions on a P.o.t.D. {Pillars of the Damned} run, and edit their base stats the following has already been fully explored.
NexusMods:
Replacing the companion_blank.unity3d files in the objectsbundle folder, works up until you expect the companions to actually walk and such. They become virtual versions of mini-kharakter-statues that some gamers use while playing tabletop games. That is their animations completely fail.
Reddit:
This process works up until the step of hitting "Import" with the companion_blank.unity3d file loaded in U.A.B.E.