If your daughter applies a boarding school, especially an elite boarding school in USA, it seems a little late for application. And please understand that an elite boarding look for a student with strong test scores such as TOEFL (100 out of 120) and 90% or more from SSAT and with strong GPA from the current school. Since an elite boarding school tends not to offer ESL, your daughter should have SLEP test is no longer administered and currently Junior TOEFL become more reliable criteria for student's adequacy for language preparedness. It means your daughter's SLEP test score will not be very useful to an elite boarding school in general without the above credentials at this time.
However, your daughter thinks other schools beyond an elite boarding school, she can still have some choices with current stats. Please contact a reliable consultant for further discussion.