Captain Tom Custer was dressed like his older brother George. He wore a blue Fireman's/Bibbed shirt, a red tie, Buckskin Pants, and according to some sources, a Buckskin Jacket. Tom did not wear the regular uniform.
Tom Custer is incorrectly shown writing the last message to Captain Benteen, when in reality; Lt. W.W. Cooke wrote the message, but he is omitted from this episode.
George Armstrong Custer was wearing Buckskin Pants, not blue ones on June 25th, 1876. He also most likely didn't wear suspenders.