What was your grade in the class? What score did you get on the AP Physics test?
How is it that you also took AP Physics at Rice?
It does sound like you were in a challenging situation, and you will have more of those in college and then IRL.
To directly answer your question, I would not write what you have proposed in the additional information section. It is virtually impossible for a student to write about a bad teacher and have it not sound like making excuses and/or complaining. I would ask your GC to cover this situation, if it is indeed a known issue at your school.
Here are a couple of thoughts I had when reading what you proposed to write:
“stress and mental health issues”- You make it sound like these things did not impact your other classes, which is curious. If they didn’t, why didn’t they? If they did, have you (or your GC) covered that elsewhere in your app?
“Had a hard time adapting to my teacher’s style”- this will be a red flag to AOs because you do have to be adaptable. And you will have profs with many different teaching styles.
Have you talked with your GC about this yet? I am interested in what they say and also in reading what other CC posters think.