Poppy Ult Mordekaiser's ghost does no damage to Poppy [Gameplay]

On aram I had a Caitlin ghost. Poppy ulted the ghost which then did no damage to Poppy.

1. Ult and then kill an enemy champion affected by Mordekaiser's ultimate.
2. Once ghost is created have Poppy ult that ghost.
3. Ghost does no damage to Poppy

Repeatability : pending - have not been able to gather friends to explore this bug