Quran's Arabic
There is no confusion about the arabic part. As the words when borrowed from other languages become the part of language itself. I was confused about other dialects of arabs present at that time among other tribes. There are words which are originated ffrom those dialects. Would we still say that even those were used by quraish so it became their language as well
Recently Ghamidi sb talk about language of Quran in recent video, it may help to understand certain aspects. Refer to Q&A session in last 30 mins of video https://youtu.be/5W8u89vqGW8?start=1h4m19s