media encoder has a DCP preset called "Wraptor DCP" that takes 2.2 gamma rec. 709 and converts it to xyz 2.6 dci white. You can also export out an intermediate and use openDCP or another authoring tool. then burn to inode 128 ext2 drive with correct folder structure. Are you sure they want a DCP and not a h.264 file on a dvd-d or bluray? You can use free encoder "shutter" to burn a h.264 with 10 bit 4:2:2 too. ame only has 4:2:0.