You can still use the export morph injection if you disable external morphs in preferences, but you'll have to edit the resulting pz2 file and set the values for each morph manually via a text editor or PFE. If you leave morph injection enabled then the resulting pmd file will be what the pz2 calls for, not the original daz morphs.

Another script, such as ColorCurvature's PML, may be better suited. Seems Poser 11's export morph injection was mainly intended for use with pmd files.