This post is canon.
Yes, indeed, the rather wonderful (and free) Barkley, Shut Up and Jam: Gaiden incorporated this piece of ridiculous screaming and insanity into its soundtrack to mark particularly “major” boss battles, but it wasn’t the first time this song made an appearance. Oh no. That honor belongs to Blue Dragon, the first title released by Hironobu “Final Fantasy” Sakaguchi’s Mistwalker studio, who more recently gave us Lost Odyssey on the Xbox 360 and the criminally overlooked The Last Story on Wii.
Fun trivia: Barkley, Shut Up and Jam: Gaiden doesn’t credit Blue Dragon, Mistwalker or composer Nobuo Uematsu in the metadata for the song’s MP3 file; instead, the artist is simply listed as “jesus christ the guy from deep purple sings this,” a reference to the fact that the vocals were performed by Ian Gillan — who is indeed the lead singer and lyricist of English rock band Deep Purple.