If offered the job, of course he'd accept it. I don't even think that's a debatable point. He could go to Alabama, fail miserably, and still be paid handsomely for the time spent plus a buyout. Then could slide into a top assistant job again after that.
The real question is how good does Pruitt have to perform at Tennessee for Alabama to seriously consider him. I still maintain he'd probably need to win the SEC at least once for them to truly consider him. Maybe he'd still get consideration if he won the East at least once, but either way, he still would need to win something beyond just some games. I can't imagine their admin and boosters turning the keys to their program over to a guy who was just "pretty good" at another school.
If by the time Saban retires the best Pruitt has done is 8-9 regular season victories but no championships, I think he'd be way down their list.