He literally explained that in the DO piece. He had zero control in the NBA. He was a well-regarded scout, but one of many. And just one of a ton of voices in the decision making process. He said at SU there are far fewer voices and he'll have a significant say.
Plus, his growth potential is clearly back in the NBA. Do well at SU and he can get a promotion to be an Assistant GM somewhere.
I'm leery of people declaring Kline to be some kind of savior. That's crazy talk IMHO. But it makes perfect sense why he's here, and what his role is. Well, it doesn't make sense if someone is willfully ignorant of the multiple explanations of that.