Even if the boat is not registered with ROAM, you can use ROAM (just fill in the registration number as all zeros - it was 5 or 6 digits as I recall), put in the rest of the info (as others have said - all US citizens), and you should be good to go. I cannot quote chapter and verse as to why it works, but repeated instances have worked just fine (I think we've done it 3 times that way).
Good luck!!!
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