BOZEMAN, Mont. — Greg Mortenson doesn’t want to talk about his best-selling book “Three Cups of Tea,” but everybody else does — including his own charity. Three years ago, “60 Minutes” and author Jon Krakauer alleged Mortenson fabricated much of the book and mismanaged the charity he co-founded, Central Asia Institute. The allegations pushed Mortenson to lock himself in his bedroom. He fought off depression and eventually underwent heart surgery. The Central Asia Institute …