Seems like you can - I converted the normal map to a height map in awesome bump, and tried what I proposed above, and ended up getting somewhere close to the original sculpt (I imagine, I don’t have the original sculpt, which is partially the reason I decided to attempt this).
Well, pretty much as I said - I put the normal map into awesomebump to convert to a bump map, and then used that as the texture for a displacement map on a mesh with a few levels of subdivision