I don't have zbrush but I would think you'd export the head, neck, and teeth if your previous attempt didn't change anything else with eyes, nose, mouth, or cheeks. You could leave off the eyes and probably the tongue. The other option you could try is to use Poser's morph brush to correct the jawline deformation. It would probably be quicker to do the correction in zbrush, but it should be possible in Poser to correct that depending on how severe the deformation.

When you've searched for threads, did you specifically search for zbrush or modelling the attempt in any general 3d modelling program? That might give a few more chances for finding answers... maybe....

The dust settled, thinking "what a fine home, at least for now" not realizing that doom would soon be coming in the form of a vacuum cleaner.