Battle of Claw Island - Trebuchet bug?
I got that message once too and thought it was bugged. When I did the mission again I found that I wasn’t holding the fire button long enough. So that is most likely your problem.
Minstrel in Training
Thought I tried that. Even left, came back and tried again. No luck. Finally found that you can just swim over and attack the boat, it has low hp. Just did that and got past the event.