Yes, I have both. The Osage Indian account (first article) places the location of the battle near the mouth of the Elk river, close to Independence, Kansas. Warner Lewis says (in the second article) that the battle was just south of Coffeyville, Kansas. Lewis deletes this location in later accounts however. (Neither town was existent in 1863.)

Various accounts have the battle occuring as far north as Neodesha, Kansas (mouth of the Fall river) all the way south to Nowata, Oklahoma. The most reliable/accurate location is near Independence, Kansas.

The event is mentioned twice in the Official Record: a letter from Elder to Blunt and in a report about a month after the event.

Where would the Confederate correspondence, anything from the headquarters of General Smith and Holmes be located?

Robert