After you have placed the bowl of flames into the statue's hands and the cinematic plays, move forwards up to the large statue of Xeria. Stop just in front of the huge statue and look to your right. You should see a small passageway with a flight of stairs going down. Go down these stairs and through the door. You should come across a teleporter and two flights of stairs leading down to the left, and a door in front of you. You can ignore this door, but on the other side of it there is a room with two sanctuary doors (combat magic and nature magic) and an armor stand to loot. Take either stairwell by the teleporter, go through a few doors at the bottom, and you should find yourself looking at some more stairs that lead up into the temple courtyard. Go up these stairs and you should find yourself face to face with the boss, guarding the shard. Kill the boss (focus fire in the middle head first), destroy the shard it was guarding, and then go through the portal behind to reach Aman'lu.

I've heard of the dragon in Act II not showing up, but this one is new to me. Anyone else ever heard of this?