In other words, religion trumps modern medicine for mental illness. I agree, but I don't see this tribe's beliefs having a special status or better probability of success above any other religion.
The problem of the article is that it ignores physiology which is evidently related to mental illnesses. A lot of illnesses have genetic factor.
I actually don't like calling inherited conditions illnesses. And I'm talking about anything including diabetes. You can't get sick with bi-polar disorder or diabetes. They're given from birth. You can't be completely cured and have to maintain yourself with medications for the rest of your life.
Next to that, there are also plenty of people that manage to wean themselves off medication after they've been on it for a few years. It's not something you're necessarily stuck with for the rest of your life.