You mean a DVD-R?
They haven't ever worked on WiiU (or for that matter, on Wiis with D3-2 or D4 optical drives - which have been used for over half of the Wii's existence by now)
You will need to install Vwii-suitable CIOS and an usb loader to load copied Wii games on a WiiU.
You will also need a hard drive (different from the one you may use for WiiU mode) or a large SD to hold the games!
This setup can also be more convenient for game mods, since you'll be able to integrate the hacks in the game!