Both side are correct but Nero's method is th best possible one without rely much on luck,Waiting until the perfect time while avoiding every bait is the best possible one-shot strategy.
If he take action in this event,The perfect time woul prolonged indefinitely
This whole setup is a trap in order to make Ability users manifest themselves and come out of hiding to save the innocents.
That's why the execution was advertised that widely.
It's all a strategy