Thank you so much, @Randy and @fishx6! I agree, I think it is definitely a juvenile Acanthurus guttatus. I have some biologist friends who were also puzzling over the ID at our local NOAA office in Pago Pago, and I'll share this theory with them.

Thank you for that article after reading the article I am quite sure we are correct with our ID!

Here is a link to a webpage that has a picture of a juvenile Whitespotted surgeonfish (you will need to scroll down the page a bit) that looks quite similar to @ProfessorPotts picture. Apparently pictures of these juvenile fish are uncommon: https://doris.ffessm.fr/Especes/Acanthurus-guttatus-Chirurgien-pintade-3525/(rOffset)/0

We have searched through all the fish in your area but could not find an exact match! The nearest we have is this one Could be a hybrid juvenile White-spotted Surgeonfish -Acanthurus guttatus