Adjustment of Status - I-485

Gah! So we had our marriage based Adjustment of Status Interview at the end of January. When I submitted the i-485 it was out of flu season so I had not yet received my flu vaccination but included a letter stating I would get one and provide evidence at the interview. I had my shot done at Costco, and brought the paperwork they provided me to my interview. Yesterday I received a "Request For Evidence" stating that my Form DS2054 indicated I hadn't completed required vaccines and I must now visit a civil surgeon. This is an expense that, after all other expenses, me and my husband are hoping to not have to go through. I can only assume the flu vaccination record I provided them has been lost or not processed? Does anyone have any advice or insight into what might have happened? Unfortunately my local field office doesn't schedule Infopass appointments anymore.
Thanks so much! My husband and I were so excited to be "done" with this stuff, we were so disappointed to receive this letter.