Just follow FIX94's guide as follows:
Grab the
current elf release of wuphax from the releases tab.
Download the
hackmii installer and put only the boot.elf from that zip on your sd card root.
Make sure to unplug any and all usb devices before following any of these steps.
Put the wuphax.elf into your wiiu/apps folder on your sd card and run it in homebrew launcher.
Press A to back up your current mii channel and inject it with wuphax.
After the wiiu restarted, go into wii mode and run mii channel, install homebrew channel from there.
To restore the mii channel just run the elf again and press B this time.
This should replace the Mii channel and overwrite any previous mod, in turn you can reinstall the Homebrew channel wich will overwrite any previous mod also and fix the broken links that stop it from loading.
Mii Channel may be your only issue when restoring but with homebrew channel back a fix will be easier.