Control the humidity, bring the temperature up if humidity control fails.
With a small heater to blow hot air over it.
That would work with a heat pump setup. Liquid nitrogen cooling is usually done by evaporating into the air directly on the processor package (as far as I know). So you would always have condensation inside the server case. Hmm, I guess a isolated duct for evaporated nitrogen to escape and heating the outside of that duct to ambient temp.
have everything that's below ambient be submerged in an engineered fluid?