Does anyone else have experience with the ADP/ADF RQ codes?

What is the 'right' way to use the Inclusive Rates (https://www.hertz.com/rentacar/renta...lusive-rates)? Are you supposed to select the LDW, LIS, FPO during online checkout or at rental, or do you do nothing other than add the code?

I included ADP on a pre-paid reservation with the Amex Platinum CDP and it added no cost. Selecting the addons that are supposed to be inclusive with RQ ADP showed the costs would be added at time of rental, more than doubling the total cost. I don't need them, but I figured it wont hurt to include the RQ.