My concern is that configuring the site to automatically redirect users sounds like they have pretty large control over the site - the kind of control that I would assume is usually limited to users with root access on the server.

Obviously hope nothing of value is lost and that there is a proper off-site backup of the content.

Edit: See Max-P's comment, it looks like the site redirection was accomplished in a way that IMO suggests they do NOT have full control over the site. We'll obviously have to wait for the full debrief from the admins.