Hi, there’s perhaps a way to do so, but if you’ve baked from a high poly to low poly mesh and still have them around you might as well use them to bake a vdm directly in that known workflow. Speaking of try this
and check his other videos.
The node group is in the linked blend https://drive.google.com/file/d/0B1mc80hFkBqcZHAxNUwtNENOTkU/view ~45MB