I'm thinking they may be more varied than 40K Orks, more like Lord of the Rings Orcs, but with the destructive styling. I'm thinking mutants.
I quite like the idea that some Orgs can be very different to others. I'm sure the mutated AG swarm may continue to change and mutate. Chaos. This would allow for many types of 'Orc'. The Org would become an umbrella designator for the Orc Archetype.
The crocodile style skin may be common to many types of Org: in the same way it was common to all dinosaurs, but not all dinosaurs where the same! So the term 'Org' would be used like 'dinosaur'. A type.