The WiiU has sold, approximately, 4 million units to date.
From the perspective of a smartphone game studio, there is very little incentive to spend the energy converting your game into a WiiU title, when your current market (iOS and, to a lesser extent, Android) dwarfs the number of WiiU customers.
From the perspective of a hypothetical buyer in the market for a games console, there is very little incentive to buy a WiiU based on the fact it has smartphone titles. Demonstrated perfectly by Blackberry, ports never work that well to begin with. They just won’t stand up against the rivalling game selection of Xbox and PlayStation. Moreover, there is a high chance that the prospective customer already owns the game on her phone.
Finally, as you have may have already inferred, from my perspective this sounds like a stupid plan for recovery. I think Nintendo have to admit that they have already ceded the console market. Rather than pleading smartphone developers to convert their apps to WiiU, I believe Nintendo should do the reverse with their own titles.
Please Nintendo, bring your intellectual property (Mario, Pokémon, Zelda) to iOS and exploit the pent-up demand for these brands on mobile.