This is going to sound ridiculous to some... But I don't think this will impact Cam Rob much at all. In fact, if may be good for him in the long run if he doesn't play this year.
No chance of injury if he doesn't play. The gun charge will be a big deal for a month or two, but by draft time next year, it will be a minor issue considering he's never been in any other trouble.
He's already proven he can be a dominant player in the SEC and has played through lots of injuries. Less milage on his knees/body could be a good thing to NFL GM's.
I'm a firm believer that guys like Cam Rob, Fournette, and other studs who've proven themselves should sit out their junior year. More to lose than gain. Ultimately 1 team wins a championship and that's a great accomplishment, but you're basically just a money maker for a university that you may or may not graduate from and most likely won't use the degree anyway... All the while risking serious injuries that could impact your draft prospects and long term health.
It makes more sense to sit out the year, train for combine stuff, hire a trustworthy management team and focus on investment strategies. JMO