I am not sure why you were marked wrong. Perhaps asking NFB for clarification will provide the answer you need. They are not always correct ... so if you feel something was marked off in error, question it! 🙂 You are correct that the author's name must be in full capitals. Without seeing the print, the braille, and the explanation they gave you, I cn't answer your question any better.
Question them and let me know what thewy have to say 🙂 Good luck!