About that SAT score. You’re no longer a native speaker of English (if you ever were). I would imagine that you spoke Mandarin at home, and if you moved back at age 6/7, at most you went to kindergarten and first grade in the US. Unless they kept you in an English speaking school, you would have forgotten your English, then re-learned it in school as a foreign language. As long as schools understand that, they may cut you a little slack on the lower English score.
Have you considered taking the ACT? The English comprehension section on the ACT is considered to be easier than the SAT’s English. Having seen SAT English comprehension vs ACT English comprehension recently, I would agree that ACT English is easier. You could prep for the ACT over the summer, take it in late August, and possibly get a very high score on it. That would solve the standardized test score part of your application.