No one really medically retires, although the team could release him to clear up a 40-man spot in the off-season. His contract is guaranteed in full, the amounts towards the luxury tax have already been computed. Regardless of what they do, he's on the books through 2026 and none of that changes.
Since it's a very soft cap, there's no reason to do the chronic NFL procedure of extensions with guaranteed money up front, then cutting the guy 2 years into what's on paper a 5 year deal. No cap, so no cap maneuvering needed.