Of the 2 options, if JJ is hell bent on Witt getting a shot at HC— then go ahead and give him the job now.
I respect Witt as a player, and he would have the respect of the guys in the locker room as far as what he accomplished on the field. Getting the job just handed to him? The hire would no doubt raise some eyebrows.
As a coach, I think he would set a culture of discipline, hard work, and high effort.
Give him some experienced coordinators and let him take his lumps on the job.
I think that is far more desirable than forcing him onto someone else’s staff.