Radio Swan, which became Radio Americas, was hardly "shadowy". It was operated by the Gibraltar Steamship Company, with offices in Miami in a commercial building just off Flagler downtown. It, interestingly, shared its office with that of AIR, the Asociación Interamericana de Radiodifusión (Interamerican Broadcasters Association) the group that unites all the broadcaster associations on the Americas.
Gibralter Steamship was a shell, owned the CIA.
Radio Swan was provisioned by regular flights out of a private air field in Miami. The facility on Swan Island, a joint Honduras / American protectorate, was a full studio and staff along with generators and a 50 kw transmitter and directional antenna. I rode on a flight in 1962 when I took a spring vacation to Miami and met some Swan/Americas staff when visiting WFAB; they took me over to the Americas offices where I got the "wanna' come along on a flight? There is one tonight...."
The station, on 1165 kHz, was pretty much 100% anti-Castro material, reporting on the daily atrocities of the new Cuhban regime such as dissidents being assassinated or imprisoned and property being confiscated and food being rationed. The staff was mostly made up of former newsmen from Cuban radio stations.
The secretary of AIR at the time was Ramón Goicochea, who had been Goar Mestre's "right hand man" at CMQ radio and TV in La Habana.
The only thing shadowy about the station was the conspiracy theory started by a Canadian DXer named Stanbury who insisted he had proven by directional finding that the station was not on Swan Island and was part of a great lie about Cuba.