Can MEDCOM override fit for duty results from a referred Department of the Navy (DON) medical base?

A service member has been identified with two disqualifiers categories to continue to serve in the military. However, one of the disqualifiers was treated over seven years ago by Landstuhl Regional Medical Center in Germany then release to Garrison and monitored by a Behavior Health Specialist Psychiatrist then deem Fit for Duty to continue service in the military. The SM has been contesting his case with MEDCOM for over a year and will be scheduled for a formal hearing with his attorney and paralegal in Fort Sam Houston, Texas. Also, the MEB included a successful surgical procedure before submitting it to the PEB. There is four successful Fit for Duty results for advance evaluation from a referred the Department of the Navy (DON) medical base and referred to other civilian medical providers during Integrated Disability Evaluation System (IDES). However, in the past, it was influenced by his former chain of command identified by his paralegal. To include, a large volume of appointments made a concern by the SM medical providers. The challenge is the Department of Veteran Affairs rated the SM 100% disable and the Army rating is over 50% To include, the SM is over twenty years in the military. What are the SM options to plead his or her case to remain in the military?