Letter of Recommendation Advice

Hello and happy finishing them college apps (and new year haha). I have a predicament regarding which teachers to choose for recommending.
I have one I know whom will write a stellar one, my APUSH teacher whom is also my Mock Trials adviser so he’s not an issue.
I am having trouble between choosing another stellar recommendation from my music teacher whom knows me really well, outside of class, and I know would serve my justice with her letter. She was sick last year and I basically ran the class because I was her Director’s assistant for choir. However music is not a “Core subject”.
The other choice would be my AP Statistics teacher, whom I know fairly well but not to the extent of my other teachers whom I’ve actually grown bonds with. All three are in so that isn’t an issue.
I cannot select my music teacher as another source because she filled the teacher one for the other colleges I applied to, and I have no way to contact her to put it in the other file.

From the website

We recommend selecting grade 11 or 12 teachers in two of the following subject areas:

English
Mathematics
Science
Foreign language
History/social studies

Recommend isn’t required, but I still have doubts. Your thoughts?

You are fine using the music teacher…the other list is only a “recommendation”…not a mandatory list. The relationship and the kind of recommendation you will get from the music teacher seems like the most appropriate and enlightening choice.