Ingrid, There's an English contemporary arts programme called The South Bank show thats been on TV for as long as I can remember.
They dedicated a whole show to WR back in 1983. I saw a short clip of this recently on either YouTube, Daily Motion or something similar.
Although Victor Bailey was in the band by then, they obviously referenced Jaco and there was a short clip of Jaco with WR at that Playboy jazz fest gig. That's my proof for knowing it exists I just hope that someone with the power let's us see it!!