you cannot overlay two materials like that. I have done this in the past by creating a second surface, slightly offset from the first, and stenciling the label onto it. You only need enough polygons to hold the label, you don't need the entire bag mesh.
thanks jean, so i have found out, pretty disappointing, i cant even seem to get a good 3d pdf out of live 3d, i suspect bc there are too many triangles, but its been lowered down all the way?