Jehannum (and his PnP group) is the creator, and actual IP owner of Dasaria.
If you're wondering about commercial purposes regarding Dasaria you'd have to discuss it with him. He hasn't been around in ages, but the name, world, etc belongs to him.
I assume the same would go regarding publishing your own stories about Dasaria for monetary purposes. It's your work, and writing. But it's still using the Dasaria label, and you'd have to clear it with him.
Someone can correct me if i'm wrong, but I hope that answers your question. lol