What are the requirements to get rewards from the event. I did it 4x on a fresh 60 with no rewards, 0, Nada. I know her damage is good (fire staff) and I was in a group. I have not finished the quest for BS and only have a T4 Azoth staff and T3 tent. What am I missing.

Did you activate the Fire Brazier to give the extra damage buff.

You need to do damage to the Adds as well as the Spriggan to get the reward.