Weren't there a whole lot of passes? Like 36 or something. Unnessarily much, in any case, but Yang Kai should simply find one with a battle-crazy commander and move there. Then he would be allowed to fight and explore as much as he wants, as long as he produces results. He obviously wouldn't be able to take the squad with him, but on the other hand, he has spent much of his life wandering alone, so would it really matter?