You no longer need to be in a group of two or more in order to complete the quest; just enter the zone. However, if you are in a group, every person in the group must have a key and have examined it in order for the group to zone in.
Steps[]
Examine the key and notice the skull and crossbones on the handle.
Find the entrance to The Buccaneer's Rest by clicking on the basement door at the base of the Coldwind Lighthouse at ( 343, -9, 830 ) Copy/waypoint 343, -9, 830.