Just block your Wii U's MAC address from WAN on your router or setup your own proxy. No need to spin up your own DNS.
Also, I will release this soon.
djbubba2002 has been messing around with web development so I asked him if he could host the files so people can just navigate to the URL as opposed to spinning up their own web server.
Also, this has only been tested on 5.0.
djbubba2002 told me that it doesn't work on 4.1. This could very well be due to changes in the library functions I'm importing but IDK.