Yes… The catechism is not infallible nor is it a dogma of the faith to believe that Muslim worship a True god.
Do you think the God of Abraham Spoke to mohammed?
No, personally, I do not. But all that means is that the quran isn’t an inspired book of scripture ( we know that there is no further revelation after the Apostles). However, all Truth and goodness comes from God. And, like it or not, there are elements of truth in Islam. There is one God, the God of Abraham, who created the world, who is omnipresent, etc, etc. Also, though they do not believe in His Divinity, the believe Jesus was the Messiah of God and was born of a virgin, etc. So, there is truth there (amongst a whole lot of untruth, from a Christian perspective) and that is of God.
Islam seems to be another heresy of Christianity, but, as Hilliare Belloc said, heresy survives by the truth it contains. On the other hand, the quran is deceptive about Jesus Christ. And that is not of God, obviously. A scary thought, indeed, that through this deception, Muslims are robbed of the saving Grace of Jesus Christ.
For me, in weighing all the arguments above (and others) I am swayed by what the Bible says about Ishmael. Remember that Islam springs from Ishmael (the Arabs and thus Muhammad are descendants of Ishmael). The Bible says that **God would make **Ishmael into a great nation. (not great in the modern sense, but great as in large). Also, remember that Ishmael is the child born of the slave and not the free woman (cf Gal 4:21 ), that Ishmael would grow to be a wild man and raise his hand against all men, and all men’s hands would be against him. And he would pitch his tents over all his brethren. (Gen 16:12). Could pitching his tents over all his brethren be eluding to forcible conversions? I’m not sure, of course. But it seems prophetic to me.
Had the Church not spoken on the matter, I might have been convinced otherwise. But I will always remain obedient to the Church, even when I don’t fully understand the issue. By the way, the Catechism is not infallible, but I thought Lumen Gentium, on which CCC 841 is based, is a dogmatic constitution of the Church. Isn’t this infallible?