You dont have to delete it.
Same happened to me, just redo the quest from the part you need.
When you get on the boat this time you dont have to fight, just hail the cpt and quest is completed.
Took me some 3 mins.
What I did: Talked to someone on the docks, went on boatride, hailed cpt, zoned out. Voila! Quest completed!
Edited, Thu Feb 3 09:07:03 2005 by BumbiRagnar