Change rewards earning from ZE1 (Hertz Rewards) to Airline miles after rental?
 

Is there any hope of changing "Frequent Traveler" credit from ZE1 (Hertz Rewards) to Airline miles (specifically Southwest) after a rental has completed? I've retroactively credited reservations to United / Southwest before but only when neither ZE1 or airlines miles was selected at the time of rental.

If it matters I'm a President's Circle member and this would save me quite a bit of money (~$2000) if I could change how a rental late last year was credited.