I tried to get this. I waited for 5 hours and I think I was present for 2 sessions but the big dragon stopped moving turned into a ball of light for a few minutes, then went back to normal. No fireworks, No achievement. This was when the fireworks was still active. (i also was standing near the holo emitter thing) I think it might have bugged out for me. Is there any possibility of bringing the fireworks back or making the helm purchasable?