Last night, I attempted to do the personal story quest “The Battle of Fort Trinity”, where you have to defend your new fort from Risen. The problem that occurred to me was at the point where I had to defend the docks from the Risen. There were a few waves that I managed to kill rather quickly, and then… nothing. I waited about ten minutes for the quest to progress, but nothing happened.
Here’s what I did to try and remedy the situation:
First, I swam all the way to the ship, destroyed it myself (didn’t take so long with my minions), and swam all the way back to the docks. Nothing.
I then swam around again, looking to see if there was any Risen I had missed. Again, nothing.
I checked other forums about this, and it was mentioned that the ship was placed too far away, and that there could be other Risen stuck underneath the docks? Can anyone confirm this, or am I doomed to stay stuck at this point of the game forever?

Thanks!