Ectoplasm vs Rescue Energy vs Catastrophe

[LOLZ]

Dusknoir Lv X (Poke Power- Ectoplasm) has a Rescue Energy attached to it and is knocked out by Gengar Lv X’s Compound Pain. Gengar Lv X is Lv’ed up from Gengar Prime (Poke Power- Catastrophe).

What happens do Dusknoir Lv X? What happens to the Dusknoir/Duskclops/Duskull?

 

[PokePop]

Depends on what Dusknoir's owner chooses to happen.
All three effects happen at the same time.
The owning player chooses which effect to use first and then the other two fizzle.