I think I have said this before but I think the answer to why we go to Othard is Zenos. They said we would learn about why he is and what he wants and how to fight him. My guess is we are going to run into Zenos and discover he has a power of some type that we cant counter. We will find out that he was once governor in Doma and then go to Doma trying to learn what the source of Zenos's power is. That would explain why Zenos would be the main antagonist in two completely different zones. One is where he is now and the other is where he has been.