The Nine Rogues Quest

[Sven Daggerhawk]

Yo there!
The server reset when I was just starting this quest and talking to Elizabeth Swan. I did not get all the instructions on what I was to do. I'm supposed to capture Luther from a Navy ship but I didn't find out how. I tried sinking several ships and didn't find him, then I disabled, boarded and killed all the Navy guys on a flag ship and still didn't even get a message saying he was not found. Could you please help and let me know how I'm supposed to capture Luther?
Thanks, Me Hearties.
Sven