I just checked, it says it's supposed to be a flute. Both are upper woodwinds, so idk if I'd even been able to tell the difference if I was quizzed, though I think clarinet tends to sound a bit more duck-like? Glad you liked the minimalism! I'm going to go with it definitely being an intentional stylistic choice and NOT the natural consequence of me waiting until 10PM the night before the deadline to realize "OH NO I HAVE NO MUSIC OR SOUND EFFECTS"