Getting rid of flotsam

Some characters developed a website on WordPress and then took the definitive version off elsewhere. Unfortunately they seem to have left a piece of junk behind that is causing inconvenience and annoyance to others (me) by cropping up inappropriately in browser searches. It links to their new site but is not accessible from it. They claim that they no longer have access to the WordPress site and therefore cannot destroy the offending page. How can one get it killed?