Why would he be in high demand with back issues? Even if he played well if he sees the field? If anything that IR should send 31 teams red flags. So his risk is refuse to tweak his contract and end up somewhere else in an even worse situation.
One could definitely argue that 3 million rollover would benefit the team next year sure, but I am all for low risks every year. You don't get better sitting on your hands.
With Witherspoon's play falling off a cliff, the risk is understandable. If his play didn't go in the tank we probably aren't even having this conversation.
So again if there is a problem area by all means try to solidify it.
I don't fault them for that. It is the moves they usually don't make that bite them in the ***.