http://www.freewebs.com/quolive/
(about 1/4 of the way down the page) in his "THE BOOTLEG BLACKLIST " section advises:
"The following recordings are fakes or wrong dates:
London Marquee 26.12.72 (non-existant date = London Marquee 26.6.72)"
I could only find two on-line references to the 2-CD bootleg that The Count reviews ... and both of them appear to stem from his review. Given the fairly extensive collectors and traders lists of bootlegs I've waded through the lack of any other mention of this bootleg is not encouraging.