It seems that the Live DVD is primarily from another show, and while it does contain footage of the Royal Festival Hall show, based on the description it doesn't seem to be the full thing. I found a bootleg of a show from the 2/24/04 but is there a recording of the original performance of Brian Wilson's Smile?
Even if it's not perfect (which would be understandable) I think this show obviously has tremendous cultural importance, and I'd love to be able to see/hear it.