[Gameplay] Sion passive bug (gold problem)

There is a bug currently with Sion passive where you can kill him and gain gold twice from it. I have two screenshots from a spectate game, where darius clearly gains 350 gold from the kill, as usual, then 274 gold from getting the last hit. The ally katarina gained gold from the assist, as usual, and as expected, did not gain assist gold from the last hit on Sion during passive.

Steps to recreate:

1. Kill an enemy Sion
2. Wait for passive to start
3. Get the last hit on enemy Sion
4. Profit

EDIT

Looking at the game again it appears that the second kill gold gain only happened when Darius used his ultimate on the Sion in passive. Later on in the game, Katarina last hit Sion in passive and did not gain kill gold, making me think this bug is only with darius or perhaps other executes.

Steps to recreate:

1. Kill an enemy Sion
2. Wait for passive to start
3. Get the last hit on enemy Sion with Darius ult (maybe other execute/reset on kill abilities)
4. Profit