My D1 college runner son had this injury last year. Crepitus (sort of like crackling sensation) when you pushed down over the tendon. MRI confirmed. Sports med (ortho) and PT and coach tried all the things you are doing - voltaren gel, ice, ibuprofen and/or naproxen orally, massage - they tried all sorts of cross training, including pool running. Everything hurt. After about a month of this, continued bad pain and aching after every cross training session, he went back to sports med - ortho, and they pulled the plug on the season and put him in a walking boot. He stayed in it for 2 months. When he finally came out of it, he was pain free at last, but it took several more months of incredibly slow progression to work back up to even a fraction of the workout level he was at before. But the tenosynovitis never came back. The rest of the year was basically lost - redshirt. Big time training errors by the coach, increasing everything dramatically right at the start of the season - hard workouts, poor recovery days, increasing both mileage and intensity big time beyond what he had ever done before, and not listening to the athlete's feedback prior to the injury that he ached and had never felt that way before.
Tendon injuries are a bitch, but if you don't bite the bullet and let them heal, they will be even more of a bitch and will continue to plague you for months or years.