Is Catholicism pantheist, holding that God includes and interpenetrates the universe?

You mean panentheist, not pantheist. Of course God is greater than the universe, because the universe did not create God; God created the universe, so He must be greater. As for God including and interpenetrating it, He includes it in His thought and in His interpersonal dealings with man, and that is the key. Pantheism and its kind are impersonal, one object bumping into another, like tea leaves interpenetrating water with no relationship between them. The difference between Christianity and every other religion is the interpersonal relationship between the creature and the Creator, which begins with our being made in the image of God so that we can respond to Him with love, compassion, kindness, and the like. Unless you get down to that interpersonal level, words like includes and interpenetrates are inert and mean nothing.