Another thing to consider is that Bill Graham was a very shrewd man who owned the venues, promotion company, and sometimes management company for these performers.
He may have had some extensive release agreements within his contracts he had the performers sign.
Additionally, these are not typical “walk into a show and video it with an iphone” clips. They are 2 (or more) camera setups with cameramen onstage and in the front row and elsewhere.
His earlier shows utilized a couple cameras on tripods.
You really don’t have any idea of how Gestapo thug Graham was about it.
He would be furious if any band played or tried to play a show not promoted by BGP.
As far as Woflgang’s Vault, they will settle.