Protecting and Enhancing Matte finishes

I got my new M235i with the satin black vinyl rocker panel decals and the matte black M Performance Rear diffuser. When I waxed the car for the first time, I was careful about not getting any wax on these black parts. The wax is Meguiar's Ultimate Liquid Wax, a synthetic polymer, and the instructions say "NOT recommended for use on flat, matte, or satin finishes."

But you can't really wax the paint where it meets the rocker panel decal without getting wax on the decal, so I just didn't wax the rocker panel at all. It's fairly easy to avoid getting wax on the rear diffuser, but you do have to be careful.

I don't like the solution of not waxing the rocker panel at all.

I'm not really sure why the Meguiar's wax is specifically not recommended for matte or satin finishes. I have some other wax, Collinite 476S, which is very high quality, and supposed to be almost like a sealant. The instructions on the Collinite do not mention matte/satin finishes at all.

Does anyone here have a product to recommend for use on matte black finishes like these? Hopefully it would be a product that is not going to hurt either the gloss paint or the matte finish, since it's going to be next to impossible to apply to one without getting some on the other...