* Why Did Ken Burns Omit Eleanor Roosevelt's Role in the Marian Anderson / DAR Scandal from his "The Roosevelts" Series?

It  cannot possibly be ignorance (Ken Burns is too bright for that) which led editors to omit Eleanor Roosevelt's role in the Marian Anderson/DAR scandal from his The Roosevelts series. 

What, then, could have caused such a significant omission? 

Eleanor Roosevelt not only resigned from the DAR (Daughters of the American Revolution) in protest over their refusal to allow a "negro" to sing at Constitution Hall, she used her influence with her husband, the President, to arrange for the U.S. Park Service to schedule the concert for the steps of the Lincoln Memorial, making it the first great civil rights protest in the country's history.