Was he supposed to drop two?

Outside the prayer room I killed the Erdtree and died at the same time. Rotten staff popped up as reward but didn’t appear in my inventory. Killed the 2nd one too by the gate and still no staff.

Top tier weapon during randomizers. The slam makes quick work of all the enemy groups randomized into the average DS2 ambush.

I just had two of these drop at the same time from the putrid avatar. I was sniping him from above and it awarded me one upon kill, but he also "dropped" an item. So I made my way down to where he died, and it was another one of these. Current discovery is 147

Interesting to note that unlike the other rotten weapons, which are just the base weapon with rot, this is a distinct design from the Staff of the Avatar. Rather than the Erdtree styling, it has the marble Celtic knot motif of the Haligtree architecture.

Weird, I just got 1 right at killing the avatar - and it dropped a second one.
The boss reset in between, probably because I used an obstacle to avoid the 50x groundslam spam.

It gave me the Rotten Staff as a reward kill and also dropped the staff on the ground. What the hell

it's pretty weird that the erdtree avatar, thing that you have to kill to get this weapon, has more HP than most bosses in the game and can literally one shot you with 60 vigor and is just placed as a normal enemy