There was a Capt. A.K. Cook in Freeman's command. He must have been a troubleshooter. In A HISTORY OF SOUTHERN MISSOURI AND NORTHERN ARKANSAS William Monks says Freeman sent Cook to Oregon County, Mo. to locate roving bands of guerillas."In some wsay unknown to either Col. Freeman or myself, they gained information, and while Capt. Cook was in Oregon county they waylaid and killed him." After the war, three men were indicted for murder in the case. Per the indictment, as one man engaged Cook in conversation another slipped up behind him and shot him. Hope this is the other fellow you referred to.