Manuel Orcarberrio was born in Cuba but moved to the United States after Fidel Castro gained power. Orcarberrio joined Alpha 66 and became leader of its Dallas chapter. In 1962 and 1963 Alpha 66 launched several raids on Cuba. This included attacks on port installations and foreign shipping.
Individuals like Manuel Orcarberrio who ran the Dallas Chapter of Alpha 66 I believe was in place to provide logistical support for Felipe Vidal Santiago when he was in Dallas. There may also have been runners used from anti-Castro organizations but they would have been on a need to know. I'm sure after the assassination, many figured out that they may have played a small role and decided to make themselves scarce.