Hi, according to the WiiLink site, it was last updated on 05/28/2025.
The current Primary DNS is: 167.235.229.36
Secondary DNS is: 1.1.1.1
Surprisingly, I just set up WiiLink and every channel seems to work properly (they still haven't updated the News Channel to another language that isn't English), including the Wii Message Board and Nintendo Channel.
You should verify you've completed each step from the official WiiLink download guide accordingly, like installing the "WiiLink Address Settings" WAD first for channels like the Food Channel and Photo Prints Channel.