Journal entry worked, and we got a nice map. I realized after the quest that I also had acquired a key, probably at the time we got the quest from the questgiver. However, the door to the area remained locked and a DM had to open it for us.
Additionally, once the quest was done, there was no particular reason to go back to the quest giver, and even though we did and talked to him, there was no way to close the quest.