Outperformed By "English Learners"

My last post on SF School "resegregation" included the following: For the sake of comparison, Thurgood Marshal HS:

I didn't notice it at the time, partially because I wasn't looking for it, but the English Learners scores are of interest relative to the "Black or African-American" scores:

English learners had a range of 587-629 with an average of 611.
Black students had a range of 468 - 517 with an average of 495.
You know what the question is don't you?

Why are "Black or African-American" students, for whom English is supposed to be their primary (or sole) language doing WORSE academically than those deemed "English learners"? Wouldn't it be the case that aside from Math problems (non-word problems) English learners would be at a significant disadvantage academically since they have to deal with the mental gymnastics of language translation and then problem solving?

Shouldn't "native speakers" outperform those with such a heavy handicap?