The girls are faster and have laser sight and cold breath, can breath in space while Nolan can survive for 2 weeks without air. And he almost dies in the first episode so he is not impossible to beat.

Omni man struggled against kaijus thatvthe ppg would casually throw into another island.

Omni man is not a dumb brute though, he has thousands of years of experience, he would avoid fighting them, or trick them.

The ppg win by brute force and if they're tactical, but if they fuck around and Nolan recognizes them for the threat they are he could bait them into a black hole or a star or something.