JHP your memory is excellent. The cruise was Voyager in April 2003, Fortaleeza to Ft. Laud. I believe that I used the 'Yellow book' facts to bolster my argument.
Now to get the topic from RSSC's archives. Radisson's statements , and the Yellow book, made shots mandatory if coming on board from a country that required them. French Guiana, for example. My friends live in Panama and know nothing about yellow fever. They travel a lot in S. America.