MRI neg 4 tendon tears or abnormalities yet exam shows ant tibialis and post tibial tendons r inflammed. Ankle Ortho does not know how 2 treat why?

It is Ok not to know. Not every specialist have to know every thing. It is good that your Ankle Ortho is acknowledging it and probably sending you to a specialist who have done this procedure. Or he may be consulting with his/ her colleague and will help you properly.
MRIs do not diagnose pain… An MRI can tell if a tendon is torn, but it can't tell if the tendon is painful. Even inflammation is sometimes overread on MRI reports. If your ankle specialist cannot figure out why your tendons are inflamed, then perhaps they are not doing an adequate physical exam or your PT is not being given the proper instructions from the orthopedic specialist. A second opinion from an orthopedic foot and ankle specialist may help.
Gentle stretching. I suspect that therapeutic exercises done in water would be helpful.