Disable iCal download?

One of the 40 site audit services we use has been claiming that the link to export current events has “an error.” As far as I can tell there is nothing wrong with the link, and the file is valid, but the client insists that it “must be fixed,” and wants the link to return a 404 so it can redirect. I’ve been able to remove the button, but the link itself still works (IE, going to /events?ical=1 still downloads the file) so the problem persists. Is there a way to disable the ?ical URI support so that it just returns the current page?

The page I need help with: [log in to see the link]