If you use that logic, every player who plays in the NFL is hurting their chance b/c they could get hurt and that would prevent them from being able to get a big contract.
You can't predict injuries, and Bell's injuries aren't of the "chronic" (no pun intended) variety. He has sprained his foot, injured his MCL in each knee, and PCL in one knee. It's not a recurring injury, they are just things that happen to people who play football for a living.
Obviously, if Bell comes back and gets hurt again, he will be in a weaker bargaining position, with regards to a new contract, but that would have been the case, regardless of whether he has gotten suspended or not.
My response was to the comment that Bell and his agent "blew it" by missing the tests he missed. While obviously not a positive, if he returns from the suspension and plays as well as he has thus far in his career, he will still get a big contract, IMO.