Your numbers are not bad. Hopefully it will heal itself. The algae growing on the skeleton will stop the healing and it will not heal over that are with live algae. I would try and move it to an even lower light area. Maybe something that has some shade. A pavona and favia prefer to same light levels, except a pavona cactus they prefer high light. It may have gotten burned and the algae grew on the exposed portion. The lower light area may also help rid that area of algae.