Yes to your Jelly Roll question - after the first volume came out, Jazzology/Solo Art either lost the rights to the LOC material or found out that they never had them - I don't know the exact story.
And I second your recommentation of the Barnes/Bocage Big 5. That's one of my favorite New Orleans sessions of the 50's - what a glorious mess it is. By that I mean that it's all over the place stylistically - Emile Barnes is playing a rough, early-20th-century style, Peter Bocage is also somewhat old-fashioned, but much more sophisticated, and Homer Eugene is basically playing bebop guitar. And nobody's worried that it might not work - they're just playing music.
I love New Orleans - they still don't care about "styles" down there.
Thanks for the great recommendation of the Barnes-Bocage Big Five 1954 ( American Music) - really enjoyed this session , my first exposure to this label. It's a bit lo-fi but worth it .