Is Josh an extreme omega like Dane? Or just a regular one?

A regular one.

Thank you! Does Yeonwoo or Josh know that Dane's an extreme omega? Or has Dane kept that a secret even from them?

That's an interesting question bc IMO Dane has never stated what he was...that I can recall. And add to confusion is his comment of not trusting omega yet he did help Josh get more inhibitor meds. And he didn't seem fazed by KP's pheromones when he went to get Yeonwoo (and even openly challenged Keith)