I found Matsunaga's Facebook page and discovered something interesting.
https://www.facebook.com/masanobu.matsunaga.9
On December 5, 2012, Matsunaga made a post about Paper Mario Sticker Star, saying the title song in the commercial is his work as well as the trumpet performance. The second commercial in this video is likely the one he is referring to in the post.
https://www.youtube.com/watch?v=WJ7x81VMm7E
He also made a comment about being involved in all four Paper Mario games, with this one being the one he was the most involved in. I wonder if Matsunaga wrote more music than just the Title Theme, especially since some other tracks feel similar like Blue Skies, White Clouds and Decalburg.