Okay, but it doesn't matter what tool ever can check whatever. To block certain user that comes from a specific host your server needs information like referrer. With server redirection the referrer from the host that redirects doesn't transfer the referrer. You can verify it if you check your access_log from the affected domain/user. If access_log contains referrer information, you can block each user who has this refferrer. If not, you can't block.