Depending on the condition, you should be able to ask USMMA medical authorities if there is additional testing you can do at your own expense in order to prove the condition has healed or gone away.
Not sure of situation at USMMA, but you should check if there is an appeal to the admissions staff or the Superintendent. At most SAs, the medical staff advises the waiver authority. For instance, the waiver authority at USNA and USMA is the Supt. At USAFA, it is the USAFA Surgeon General, thus no ability to appeal to admissions or the USAFA Supt.
My DS was not successful appealing waiver denial decision by USAFA, but did receive a medical waiver from US Army Cadet Command for his 4yr AROTC national scholarship.