I am not certain of the use of these terms so research on your own -
There is the issue of whether the TE is tendinitis (more inflammation?) or tendinosis (healed tissue with defective scar tissue, fibrosis..?...) or some mixture of the two conditions. Obviously this gets very complicated, unknown, and risky especially if the elbow is still under heavy stress with exercises or tennis.
Tendinosis, Eccentric treatment is mentioned as an area of research -