Sorry for the looong wait! Finally found a decent quality of Green Boys on Music Station. They had a talk with the emcees, and sang Kiseki followed by Koe with (I think) recorded vocals in the background. This is not the full cut because they appeared too many times in the back when other artistes were talking as well as in the small window at the top right-hand corner. Other than their talk and performance, the cut also includes the opening, talks with Bruno Mars and Nishino Kana, and ending.
Green Boys’ Cut
(password hint: the url of the homepage)
MS also tweeted a short message from the boys right before their performance. Didn’t Suda Masaki look tired?
— music station (@Mst_com) January 20, 2017