Yes, promo codes and Raise Cash can be used on the same order to purchase discounted cards on the Raise Marketplace. However, promotional codes cannot be combined with Raise Cash when purchasing CashBack cards.
Only Raise Cash can be used towards a CashBack Order. By using Raise Cash on a CashBack order, this alters the earnings amount. This is because the CashBack rate is based on the amount paid out of pocket, not the card value. The applied Raise Cash deducts the out of pocket price which may deduct the amount you will receive back.