Comment by floxy
I'm not an expert in this area at all. But I was under the impression that for some of these schools, that is the case. My understanding is that some (many?/most?) Muslims believe that the Quran was a direct revelation from Allah in Arabic, and so translations are somewhat suspect, risking incorrect interpretations from humans.
I know that Muslims believe that translations of the Quran are of a lesser status, but I didn’t think that would extend to not even explaining their meaning to the students.