Two questions.
Does this “Brando Island” belong to a recognized (has a US diplomatic presence) nation?
Does this nation in question have an extradition treaty with the US? Preferably one with few, if any, restrictions o who can not be extradited.
French Polynesia is a non-extradition country.
Most of Tetiaroa is private property. from wiki: “In 1904, the royal family gave Teti’aroa to Johnston Walter Williams, the only dentist in Tahiti...Brando eventually purchased Teti’aroa’s islets (motus) from one of Williams’ direct descendants, Mrs Duran. The reef and lagoon belong to French Polynesia.”