Planet Hollywood has always been on the
DDP. It's one of the few that's always taken it.

On the voucher itself, it had always been stated that it can not be used in conjunction with any other offer including the DDPs. I don't know what they are allowing now, but in the past you could use the $15.00 voucher to order an appetizer from the bar, pay for it, wait to be seated, take the appetizer with you if you weren't finished,
then use the DDP to order your entree and dessert. It had to be two separate transactions though. (One note-the last time we were there, several of their desserts were for two people and two people on the DDP had to order them in order to get them.)