Banu Hashim are direct descendants of Ismael. Not Jews, Sons of Abraham. The Jews in Mecca were monotheists waiting for the coming of the of the prophet Jesus was questioned about. The Quresh were the tribes that ran Mecca. They had fallen into idol worship.The Quran's revelation began 15 years before Muhammad made hijra to Medina. Many Jews who knew their books recognized Muhammad as the Prophet who was foretold of in their scriptures. They converted. But other than that, your spot on.