This is where you went clintonian.
Muslims are those who follow Islam. It doesn't matter if Islam is not mentioned as that is the religion being discussed is you're noting Muslims.
CCC843 says "The Catholic Church recognizes in other religions". There is no switching of gears as if we're going from talking about a people and now religions.
BTW, while we're at it, this heading is CCC839 "Those who have not yet received the Gospel are related to the People of God in various ways." The Jews HAVE received the Gospel, for the most part they've rejected it. This whole section needs a traditional rewrite. Precision doesn't seem to be high on the list of goals this time around.