وَمُسْلِمُو مِصْرَ
Translation: And the Muslims of Egypt.
وَ: conjunction.
مُسْلِمُو: coordinated with «غُلَامَا», nominative with wāw as a sound masculine plural; it is muḍāf, so its nūn has been dropped.
مِصْرَ: muḍāf ilayh, hence genitive; in this reading the sign is fatḥa because the proper place-name is treated as a diptote.
Nuance: A three-letter feminine proper name with a consonantal middle may also be declined. Thus «مِصْرٍ» is another valid classical treatment. The printed book does not fix the final vowel here; «مِصْرَ» is one explained reading.