Baking texture, vertex colours simultaneously w/ seperate UV maps, alpha

  • I imported a PLY model into Blender with vertex colours and a UV-mapped 192x114 texture.
    (There is unavoidable vertex overlap in the UV map.)
  • I cloned the tris containing both the UV-mapped texture and vertex colours to another object,.
  • I marked seams on the original object, unwrapped and then baked the vertex colour UV map to a 1024x1024 texture.
  • I associated materials to each object and textures to each material with appropriate settings for shadeless rendering. (The texture requires alpha)

But now I’m unsure of how to bake the texture and vertex colours into one texture, including alpha.
Is this doable, with an add-on or otherwise?