How did he become a COO again???

At the very end of the film, it reported that Whitacre is COO & President again at another company. People of power whom know him obviously do not view him as untrustworthy or as a liar. They obviously trust him enough in order to have hired him a few years ago, and then promoted him to a COO. It has to be one of two possibilities: Either the movie did not portray Whitacre in the same light that powerful people view him as--even the FBI are talking extremely favorable about him in recent interviews. Or powerful people viewed him to be mentally ill twenty years ago while at ADM, and today view him as treated and mentally stable. It has to be one or the other, because one cannot reach such a powerful position that Whitacre holds today unless everyone in that organization trusts him completely. The Whitacre portrayed in the film would never have become a CEO ever again, and certainly not so quickly after serving 8 or 9 years in prison.