I only read the first page but its obvious no one really answered your question there.
1)The install base of the Wii U is not large enough for a game like Donkey Kong to sell amazingly well.
2) Having third party attracts keeps loyal Nintendo gamers on Nintendo platforms solely, but also attracts other gamers who primarily like third party and exclusives secondary. The chances are higher that they will actually buy an exclusive if they have the console. If Nintendo has no third party this variable goes out the window.
3) Nintendo needs to revitalize marketing for kids with Donkey Kong because it was mostly kids in the 90's who grew up with Donkey Kong as protagonist.
4) Remember that the possible sales legs of this game might exist because more people will purchase Wii U's down the road. Nintendo doesn't sell Blockbusters. They sell games, so let the sales come.
5) Nintendo needs to sell the DS gamers on the Wii U because that might be Nintendo's saving grace.
