It’s possible that they want updated vaccines. When she did medicals, a vaccine may have not been available in the country. My husband’s vaccine sheet said varicella (chickenpox) vaccine wasn’t available in the country. I sent a message to his physician and she ordered labs to do a tiger test to see if he has immunity (haven taken the vaccine long ago). He was immune and we provided that test result to a civil surgeon nearby including that he has taken the most recent flu vaccine. The surgeon signed the I-693 and provided us a sealed envelope for us to provide for the RFE response.