Leave it silver or gunmetal. Silver/gray/gunmetal is a good midtone that will be slightly lighter than camo yet not take attention away from your wheels.
If you want your white wheels to stand out, don't put white anywhere else on your car or at least use sparingly. White will sort of act as a highlighter on a camo, so any white you add will pop out.
Think of a visual heirarchy. The first thing you see will be whatever pops out first (white wheels). If there are too many elements popping out, your eyes won't know where to look.
Working with 3 colors is a nice balanced color scheme to begin with: one dark (camo), one midtone (silver), and a highlight (white). I think the addition of black will be too many colors. OK....that's my color theory lesson of the day