Daniel R or Sam T. Duniphan

Trying to find out anything I can about Daniel R. (b 1842, white) and Malinda (b 1822) Duniphan (Duniphin).  I believe Malinda was previously married to Isaac Allen and I believe they were both full blood Native American; Chickasaw, Choctaw or Cherokee I thought.  Malinda's maiden name may have been "Sides".  She had a son with Isaac named David and a son with Daniel named Sam T. (my g-grandfather, b 1862).  There is family rumor that they also had a girl, but I can find no evidence.  Family legend indicates Daniel and Malinda were both killed in Indian Territory, OK in an uprising, at which time David and Sam fled different directions.  Sam wound up in Stoddard Co, MO.  I can find a David on the Dawes and Pawnee rolls that is the right age (b ~1853) listed as full blooded, but can't find any previous trace.  If it is the correct David, I am puzzled why he is on Pawnee rolls.  Any ideas where to start?