I almost forgot that Injustice for WiiU released that week. Didn't make it in the top 40 and is 5th in the WiiU charts behind the stand alone version of NintendoLand. Probably just below 1.000 units.
That might be optimistic. Even if Injustice only dropped 50%, we would be looking at around 700 for the Wii U version. If it was a 75% drop, that would mean only about 350 sales for the Wii U version.