Sorry, buddy. Rockytop does refer to a murder. The two strangers by description were "revenooers", southern jargon for government revenue agents specifically assigned to chase down moonshine still operators and arrest them or shoot them. The moonshiners returned the shooting favor with gusto. The Rockytop refrain on this is indeed talking about those agents being killed while looking for moonshine stills in the Rocky Top area.
When the song was made originally, the author surely meant it to be humor though the behaviors described were realities that existed. Finally, it's not unusual, I'm sorry to say, to see violence in American artistic work. Whether you're talking about the song Stagolee, TV westerns, Mighty Mouse or Popeye, Toy Tommy Gun as children gifts, movies, or Rocky Top. So it's no surprise like it or not, truth is the good old USA's inner core is historically violence prone and manifests itself in various ways. Including the current anarchy on our streets and in our schools.
Thanks. VN is awesome I get football news and history lesson lol