Once again, your logic is going to save somebody from a potential issue. Even though I don't think it matters really, I'm going to make secondary DNS 0.0.0.0 also.Yeah, tbh I'm not sure if there is a better way. It really depends on how the Wii U is coded to work. And I'm not going to be the one to test it out
To think of it logically: if TubeHax DNS goes offline, the Primary DNS fails, right? So that's when the Secondary DNS is supposed to kick in.
Option A: If it is also TubeHax DNS, its going to fail too. Then what? Is the Wii U coded to go to "Auto-Obtain" mode? If it is, you'd update.
Option B: If the Secondary DNS is 0.0.0.0, it should just keep you from accessing the internet at all.