I had an Aunt and Uncle who knew him well, they played for the Son’s of the Pioneers when he was a regular. I don’t know if this is Ken singing but my Aunt and Uncle were playing during this recording. Doesn’t sound like the lead singer is Ken, he might be in the back ground. They said he there.
https://www.youtube.com/watch?v=eMqKv7BOg_s&t=33s