The contact number is 919-382-3149, and ask to speak to customer service. One of the reps name is Bryant Hailey, the other is Russ Bennett.

I just went through this last month with the purchase of a 2005 150CC, and at first they would not transfer the warranty. They told me that the purchase has to be either from a Triumph dealer or directly from the FIRST owner. The warranty is only transferable to the second owner of the boat, regardless of the boats age. I was buying from a dealer who was not affiliated with Triumph, but, I argued the point that the boat was never transferred or sold to the dealer, and that he was acting as a broker for the seller. Finally Triumph gave in, and required that I sent them a notarized bill of sale from the first owner showing the sale to me. That dealer was able to procure that for me. I also had to send them a $200.00 "transfer of paperwork" money order or check.
In my opinion, if you will be the second owner, and the bank has never taken legal possession of the boat, it should fly as long as the bank or your car / dealer can get you the notarized bill of sale.

Good luck