No problem reserving through UA using the CDP, UA promo code, and Hertz # gold number. On my two recent rentals, each received 500 (1 rental day) + 1500 (united.com booking bonus) + 750 (1K bonus) + 3000 (Hertz summer offer) = 5750 miles! Make sure in your Hertz
#1 gold profile, you select earning airline miles instead of gold points.