Are you talking about the badges? If so, then it sounds like our best bet would be to remove them, paint them black and put back on.
Yeah if you can find some caps to fit and stay in there. If not, get some small bolts to put in the holes and put nuts on the back side so they stay secure then put some caps over the head of the bolt. Just an idea The holes aren't that noticeable unless up close (-10ft) or looking for them.you can possibly find a cap that can lock in. other than that, i dont know of anything that will cover or fill the holes.
maybe spray paint the screws that held the inserts in black and then put the screws back in? idk