Uv unwrap cell fractured parts

I have a mesh(green) that I ran through the cell fracture tool, which assigns new faces (yellow).

The green part of the mesh is already unwrapped(red box), and I do not want to modify them at all while unwrapping the yellow sections.

Is there a way to unwrap them so that they are one piece without having to do it manually?

Select by material and make another UVs /unwrap just for the selection?

That leaves the uvs for the yellow faces separated from the uvs for the green faces like in the third image. If that’s not possible, I can make it work if the yellow part uvs are rotated in the same direction as the green part uvs.

Yeah, i guess i was reading all over the sentences… However inside usually is different from the outside material.
You can rotate any UV island separately of course. L selects like in 3d view. Dunno if some stitching or welding might help and that’s a lot of manual work anyways.

It’s about 160 pieces for this model, and I have several models that I have to do…

You don’t say much about what exactly you put on UVs: join shards temporarily and use smart project. I already know that’s not the option due to whatever reason…But when you separate them again by loose parts each will have this UV map. And maybe selecting faces and mask/stencil 3d painting would help.