My bug story is similar to this guy's:
I was near a shipwreck and the encounter with the pirate was ruined. Basically, as the encounter forced me to load the ships, only my ship was there and I could only choose an option to leave or search the shipwreck. It was clearly bugged, forcing me to leave the screen via the "Embark" button on the top. I am on an ironman save so I can't even reload. I don't know what to do... Is there a way I can spawn him again?