I assume you can use 2 different cards. I have used prepaid Visa's from rebates with my regular Visa before. On another trip, I split between Disney Reward Dollars & Visa. Can't see why this would be any different.....
I was able to do it online with 2 different cards in 2 separate payments on the same day - with debit cards from the same account - we have a daily spending limit on our debit cards so I couldn't do it all at once. Paid half of our balance during my lunch hour than used DH's card to pay the rest that evening.
From what I remember when I was going thru it, I believe there is also a way to use 2 separate payments in 1 transaction.