You don't really have too many options.

You ruled out EXP in your thread over at DAZ, .PMD are an issue in DS4, a custom CR2 with just a readscript and your morph channels wont work for the same reason you gave for EXP.

You can make new channels in a loaded figure with python but that wont work in DS, you might be able to get someone in the funny handshake gang over at DAZ to make you a DS version, but don't be too surprised if you get ignored.

Which pretty much leaves you right back where you started with the PMBCC & PMBDC channels.