I booked and paid for CRT before booking the DDP and I was told they would refund the money when we arrived at the podium back onto the card. If that's what I wanted them to do.
But since it was 2 table service credits we decided we would rather do 2 other meals and just pay for CRT OOP. It was a better value that way.
And yes any meals that require a CC to hold them will still require that even with the DDP. I had to give them one for the fantasmic package and the candlelight package.