What about what was said was dishonest?
The caller suggested sending in some troublemakers into the crowd. Walker said, "we thought of that" and went on to detail how it was unnecessary and would be counterproductive. He should have instantly recognized the suggestion as morally reprehensible and said so in clear and forceful language to whoever was on the phone, or anyone else, at any time and place.
Walker's reputation was that he holds and adheres to the highest moral standards. Standards that most certainly include refusing to engage in such dishonest conspiracies that amount to bearing false witness. He should have flat out rejected any such suggestion and made it clear that he would not tolerate any such dirty third world rat behavior from his ranks.