Complex sentence: The recording was originally for the purpose of a demo to shop the song, but RCA got a hold of it and Dixson, who owned the master and produced the demo, agreed to let RCA release it.
Split into simpler sentences: The recording was originally for the purpose of a demo to shop the song. But RCA got a hold of it and Dixson, who owned the master and produced the demo, agreed to let RCA release it.