That thought occurred to me, but there's no indicator on the song list which song is played where - just a plain alphabetical listing. This wouldn't be a problem... but the phone isn't accessible during the cutscene in question, which means there's no way of checking the Now Playing status. Hence asking if anyone knows which song it is, in hopes I won't simply have to guess based on the lyrics and go through that encyclopedic list. Thank you, though.
EDIT: found it. "Shake it Down" - an AI generated track by the dev. Ah, well.