rfc4eva, I am not a Velocity user, so cannot answer your question fully. But my comment is that once in the USA there are many options to get to sth america. For example Copa (based in Panama) has very reasonable prices and covers essentially all sth and central america, including the Carribean. They have a huge network. They only run small aircraft (single aisle) but have the network and the prices. If you were going to do economy I would buy direct with them, if you wanted business I would buy Lifemile points and redeem a J fare - Copa have superb availability and almost negligible co-payments.
Perhaps someone more knowledgeable of Virgin can assist you getting a ticket as far as Panama?
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