The DMCA was signed into law in October 1998, but rarely enforced for the first few years it existed, at least at the discussion board level. People posted what they wanted to and only took it down when they got caught, like Jams who got caught on more than one occasion posting material she had no right to make public.
No one wishes they could find it more than I do!
As for a vidocq report being at one time available online and at one time discussed online but now vanished along with all trace and reference to said document and discussions? Surely, everyone can understand how unlikely this seems and how those of us who have never seen the report or any reference to it or discussion of it might have doubt?