I don't recall seeing or hearing anything from that gig. In fact the only two Gram era Byrds recordings I know of, is one from Rome and one from London.
I would suggest you to check the 'Byrds Flyght' website. There's discography of unofficial Byrds recordings.
BTW their show is mentioned at the Gran Ole Opry's website as one of '80 Unforgettable Moments at...': [
www.opry.com] That site says Hickory Wind replaced Sing Me Back Home.