I was able to find the stream using the following search API call, I added an extra letter just to limit down the number of responses: https://api.twitch.tv/kraken/search/streams?q=breadn
I even tested searching for the stream in my personal application and was able to find it using: https://api.twitch.tv/kraken/search/streams?q=bread
Also, calling the actual stream using the following API call worked: https://api.twitch.tv/kraken/streams/breadnbuttergames
Using the URL you originally provided I was able to find your stream as the 38th stream listed. Note however that I had to use the offset parameter with a value of 25 since the default list only returns the first 25 streams and at this moment there are 57 streams of Super Smash Bros. Your stream is there, it just wasn’t one of the first 25 streams in the list.
For reference here is the API call that let me find your stream: https://api.twitch.tv/kraken/streams?game=Super+Smash+Bros.+for+Wii+U&offset=25
You could always use the limit parameter to find all streams, assuming there aren’t more than 100: https://api.twitch.tv/kraken/streams?game=Super+Smash+Bros.+for+Wii+U&limit=100