There's something that bothers me about the story. I don't want to blame the victim, but was there any forensic evidence when it happened in seawater? Or any other evidence? Or was it just an accusation?
There are nuts out there who make things up. Not sure what happened here. Sounds true just from listening to her on the tape. The next question is what do you do if it happens in an isolated spot and you can't prove anything, just believe the first person to say something? What if they are contradicting each other?