I've got another idea... import your OBJ (the one that's fresh out of Blender) into Poser as a prop, uncheck everything when you do that... then go to the Grouping Tool and hit the “spawn prop” button... exit Grouping Tool... and select that newly spawned prop and export it as an OBJ... check "as morph target" uncheck everything else. That's your new morph target file... and this time should load properly onto the head as a morph.