I had a very similar problem myself in March 2003, when I wanted to remove the very out-of-date GEDCOM I had posted seven years earlier.
I eventually received a response from Stephen Rowe, Isle-of-Man.com Administrator who removed my GEDCOM file for me.

I do not know if this gentleman is still in charge. The name and contact address of the webpage adminstrator ought to be clearly marked on every webpage.

Kind regards,

John Ball
wfha@clara.co.uk
http://home.clara.net/wfha/