LOL - you do not know football if you don't think he can't go get a top notch DC job sooner rather that later. I promise you no one in his profession is going to begrudge him getting every nickel he can out of UofSC. It is a brutal profession, most of these guys are friendly for the most part with one another. They all get it, you either win big or you get hammered by your fan bae. You sometimes get hammered even when you have won big and then lose one along the way.
Coaches have a fraternity, they look out for one another. Will is a hard worker, and a better than average recruiter. He has a dynamic personality, he just isn't a great head coach. I promise you Will bounces back quickly and will be at an a top 20 program as a DC in short order. He may go the Saban rehab route and make $25 k per year while Tanner pays him millions, but it won't be long before he is back at the helm of a defense.
Besides, this job, isn't viewed well, it is a tough place to win. Let's be real, who has one big hear? Two guys, ever. Most coaches who think they can do better don't want this job. It has to be a guy that thinks he is skipping a step and it is the chance he has been waiting on. Even then, this is a stepping stone. If he has a lot of success, the allure of one of those top 10 jobs is usually too good to pass up.