Catastor vs. Grand Mole

Neo-Spacian Grand Mole attacks Ally of Justice Catastor.

What happens?

Chain Link 1: Ally of Justice Catastor
Chain Link 2: Neo-Spacian Grand Mole

Grand Mole bounces Catastor and Grand Mole back to the hand. Catastor then fizzles.
Reasoning: Catastor is mandatory and Grand Mole is optional. Therefore, Catastor must be placed on the chain before Grand Mole is.

Since Catastor effect is mandatory it becomes CL1,
Mole becomes CL2, Resolving backwards:
-CL2:Mole eff activates sending both monsters to their respective hands.
-CL1:Catastor eff fizzels since both him and his target are gone.

TL;DR: Mole activates first.

EDIT: Ninjad! Also hasnt this question been asked like 5 times already?

Ahh i see now, i forgot that grand mole was optional. Thanks for clearing this up