Verna Arvey, wife of composer William Grant Still (who based a work on the fruits of EH's folksong research), interviewed Elsie Houston for Etude in the 1940s. She also shows up in Arvey's memoir/biography, In One Lifetime. Here is the passage:

The night Elsie Houston came to be interviewed for Etude had a party-like atmosphere, because Loyd and Betty Rathbun and Kenneth and Adelaide WInstead brought her to our house. Loyd, the oboist) and Kenneth (the bass player) had been in Karl Krueger's Kansas City Philharmonic Orchestra when Miss Houston was soloist there. They had a recording made during her performance. Miss Houston (who, incidentally, was one of the most sensitive and professional performers we had ever met) didn't seem to be particularly interested as this recording was playing away in the backroom. But when she heard herself speaking (announcing an encore) her mood changed. She stopped talking. jumped up, ran down the hall and paid close attention from then on. She had known in advance how the rehearsal part of the program would sound, but she had no way of knowing how the unrehearsed part would come out. It was a novelty to her to hear it as the audience had heard it on the night of the performance.

It was tragic that an artist who had so much to give should have wanted to take her own life, but she did. She was too sympathetic and impressionable; she took to heart everything that happened in the world. Shortly before her death she wrote to us of "The mess we are in--all of us." (135-136)

Two things of particular interest. One, the character sketch--the hyper sensitive artist with a pessimistic outlook. Second, the recording! I wonder if it still exists!