I really dont know where the issue is.
Please try these parameters in your config:
As you can see only porteus-kiosk.org (and subpages) are allowed. If you try to open google.com or any other webpage then you'll get access denied picture.
It should work the same for your website.
BTW: setting up the homepage to porteus-kiosk.org and whitelisting something else (like in your config posted above) will produce 'access denied' picture.
Please add [Solved] to your thread title if the solution was found.