There are two possibilities here, and if there is a complication you can probably fix it.
If you are going to get
DDP, you have to get it for the entire duration of a reservation. So part of the answer to your question depends on whether you have
one ressie for your stay
or two for the split stay.
If you have two separate reservations, there is no question that you can get DDP for the DVC portion...provided you are staying on points. There is no park ticket requirement, but you will have to get it for everyone in the room for the entire 5 nights. If you get DDP for that portion, keep in mind that the DDP credits expire at midnight the day you check out of DVC...so you can't spread them over the entire duration of your trip.
If you have two separate reservations, whether you can get it for the CSR portion depends. DDP is a package which includes a room at a certain rate (usually rack), at least a one-day base park ticket for each person, and the cost of DDP. If you have two separate ressies, but you got CSR at a discount, you will have to change that to the required room rate and add at least a one-day park pass to be eligible for DDP. It may or may not be worth it.
If everything is currently in one ressie, you can probably split it into two and only do one of the above options.