To begin with, George Caleb Bingham did not own the building, it belonged to his wife Martha Lykins. She was born in Kentucky, was an orphan and raised by her grandmother. She later lived with her sister in Jefferson City, Missouri at the age of 16. She maried Dr. Johnston Lykins in 1851 and they moved to Kansas City. He died in 1876. She was a Southerner by birth and sympathized with the Southerners even to the point of establishing a Confederate Widows' and Orphans' Home. Then she married George Bingham June 24, 1878 well after the building collapsed.
Sources: Richard S. Brownlee, "Gray Ghosts of the Confederacy: Guerrilla Warfare in the West, 1861-1865", 43 & 118; Joanne Eakin & Donald Hale, "Branded as Rebels", pages 276-7; Rose Mary Lankford, "Encyclopedia of Quantrill's Guerrillas", page 147.

You can read about Bingham in James A. Browning, "Violence Was No Stranger: A guide to the Grave Sites of Famous Westerners", 24; Brownlee, 44; The Columbia Encyclopedia, Third Edition, 218; Eakin & Hale,277; Lankford, 17; William A. Settle, Jr., "Jesse James Was His Name", 79; Floyd C. Shoemaker, "A History of Missouri and Missourians", 230; and Paul I. Wellman, "A Dynasty of Western Outlaws", 48-49. These are the books I found my information in.

After the war, he investigated the bombing of Zerelda James Samuel's home, the mother of Frank and Jesse James. After his death, his paintings were auctioned off and the proceeds went to the Confederate Home in Higginsville, MO. He was also a Southerner by birth being born in Augusta County, Virginia.