The first update is in Deep Sebilis: Kill an 80^^^ "a waterlogged wraith"( 22, -132, 173 ) /waypoint 22, -132, 173 which has about 120,000 HP's and does crushing dmg.
Jump into the water and swim through the underwater routes, see discussion page for information on getting there if you need it
Second update is in Chardok. Take the sokokar then backtrack to the water room. Kill an 80^^^ "a drenched zombie" ( -481, -85, -336 ) /waypoint -481, -85, -336
Third update is in Charasis: Vault of Eternal Sleep. Pick up the note located in Charasis:Vault of Eternal Sleep, ( -12, -7, -110 ) /waypoint -12, -7, -110. This is the clue to find the last pirate and is needed to spawn the next update
Head to Chelsith, When inside go left to ( 291, 7, 290 ) /waypoint 291, 7, 290 here you will find The Pirate Jones (80^^^) (about 144,000 hp and does crushing damage)
Hail him and go through his dialog, at the end he will attack you. Kill him and get the map update.
This quest is part of the Swashbuckler Epic Weapon Timeline, and can only be started/completed by a member of that class of at least Level 80.