Gluing a pice of wood so that the tuners are not swimming in air.
The production model will not have this, that will have a jig to layer carbon fiber over, something like this
That would be a bit too labour intensive for a 1 time prototype (make the reversed shape plug, seal the pores with epoxy or thick varnish, wax, make carbon fiber part).
If you do it with a jig like this, you would have the cilinders and the headplate in 1 piece. If you use a steel plate or aluminium, you can let your logo shape raise out of the baseplate, and the carbon fiber will go around it. The cured part will have a hole with the shape of your logo inlay (no routing needed), just glue your logo in...
That would be a job for a CNC machine, not many people are that accurate with hand tools., and you want the mould to last for a long time, so carving it out of wood isn`t an option really...
The main goal is finding a good tone balance between the warmth of cedar wood soundboard and the clarity of carbon fiber.