Obviously not having McCoy would really hurt the chances of the Bills advancing in this game. If he can't go, Tolbert, Murphy and Jones would likely share the workload. It sounds like even if McCoy plays he won't be at full strength.
BUF RB Mike Tolbert - Week 7 Fantasy Football Outlook
Week 7 vs. Tampa Bay Buccaneers
Mike Tolbert is clearly the backup for LeSean McCoy, but that does not produce many touches because McCoy's usage is top-five in the NFL. Where Tolbert has some fantasy value is in goal-line situations. He only has 1 touchdown but will get those opportunities should they become available.
Since that is Tolbert's main strength, it's not enough to have him in a starting lineup, and he is even a borderline roster player at this point.