what do i do with items for Siege of the Dragonspear?

[swordfish]

korlasz's key, tomb key, and ornate headpiece?
I got them after I killed Korlasz..

[D'amarr from Darshiva]

All for locks to rooms or chests in this prologue dungeon Korlasz's Crypt. The ornate headpiece is the second part of an item you need to reconstruct for a side-quest in this dungeon.