Okay, from that link, which is a completely subjective "metric," 4 of the 6 people ahead of him already have their jerseys retired. That list has Ron Widby ahead of him, which is a joke, since he mostly played football. Only scored 576 career points. Reggie Johnson was a good player, but hard to argue he had a better career than Lofton. Lofton was a 4 time All-America (two 3rd teams, two 2nd teams), which I imagine hasn't been done often at UT if ever (Note only a Rivals 3rd team All-America as a Freshman). So according to the list he's certainly been SEC player of the year, still holds a major statistical milestone (Most 3 pointers in SEC history by a wide margin), arguably a first team All-America if you count the Wooden one, if not he would just have to be selected by a nominating committee.
Plus if you factor in his story like playing through cancer treatments and bring Tennessee basketball back into relevance, I would find it hard to believe a nominating committee wouldn't select him. I was hoping Admiral would be the last person to wear the #5, but obviously not. Also, again going back to your list, it seems pretty clear that Lofton is the 5th best player in UT history, with the 4 ahead of him having their jerseys retired. I see no reason to think that he shouldn't be on that list.