That was the scam that Peter Villiotis ran in Panama through his privately-owned Pan American Seaways company along with a Panamanian tour company named Aventuras 2000. Tickets were sold and people were expecting the ferry to actually operate when in reality Peter never had control of the Nissos Rodos. It's a perfect example of what a con artist Peter is.
Read this articles and the comments that follow it. Peter actually had reservation agents responding to inquiries and none were telling people it wasn't happening.
I previously found a travel chat forum in which one mad discussed having bought a ticket for himself and his truck and that they wouldn't refund his Visa card. He was eventually able to get a refund by having Visa reverse the charge. I'll keep looking for that chat room as you can plainly see that people believed the false service that turned out to be a scam.