*sigh* even when she's trying to yell she's quiet and boring.

Was there just literally no one else who wanted/was qualified to do the job?

I'm glad you asked! Commentating is an elective and due to how frequently matches are held vs. the students needing to attend class, there are actually many students who do it. Performance determines what battles they sit in on; Odina is considered the best of the best and is partnered up with Dublin, so they commentate most (but not all) of the big league matches (4v4 and up). They have a few stand-ins for when they're unavailable, especially given Dublin was part of a 5v5 team. He's skilled but can't commentate on his own matches!

Meanwhile Coraline here - well, her performance speaks for itself, so she commentates the matches with the smallest audiences. She's likewise just part of a rotation, so there are definitely students who do a better job than she does. I'd estimate she has...fifteen other students to surpass before she overtakes Odina and Dublin, but five of them are paired up.