I may now be able to answer my own question and invite others to weigh-in. See Union Provost Marshal File of Papers.....M416-035 image # 543-556 for "Report of Boards of Investigation of Claims for Damages &c committed by Troops Under His Command in Pursuit of Rebel General Shelby". This is a group of 14 documents regarding complaints by Maj. William Gentry 5th Prov. E.M.M near Warrensburg for losses he incurred from Kansas troops under Ewing in the pursuit of Shelby. The investigation began in Nov. '63 and appears to be finalized (?) in May '64 but had Ewing busy in March and April 1864 especially in the era I am researching of the first couple weeks of April 1864. I am not actively researching this aspect of Ewing's career now that I have this information.
These files can be accessed through the Missouri State Archives website. Bob