Just a wild guess, but since a generator fail results in loss of power to the fuel pump when in NORMAL, I'm guessing that RECOVER connects the fuel pump to an essential bus or battery bus (not sure of the electric system). This makes a bit of sense wrt the use of the Normal/Recover switch since this means an engine failure at night will require fewer switches to recover the engine.
Again, just a guess. I've never flown the TH-57C.