This quest is not available in game.
Return to Stormwind City.
The world's soul is secure... fer now. I can hear Azeroth again, although her voice is still weak. The elementals on the surface above have calmed down. Even using just a fraction of its power, the Heart of Azeroth brought stability tae this place. Ye need tae return tae Stormwind and inform your allies of what transpired here. Remind them that no matter what happens with the Horde, our world must be saved. We'll speak again soon, <name>. The battle fer Azeroth has only just begun.