I believe what happened is that Valve said something along the lines of: "We are a little concerned that Nintendo might object, you can only continue if you get

I believe what happened is that Valve said something along the lines of: "We are a little concerned that Nintendo might object, you can only continue if you get an official notice from Nintendo saying they don't object." It's entirely possible that Nintendo don't care, but the chance of Nintendo agreeing to go on the record about such things is basically zero.