That happened to me as well. Used silicon. As mentioned, the result is ugly but you will still have a working diffuser.
I don't know super glue, but (by its name) it will certainly do it. However, make sure this super glue is something that can be undone some how. The diffuser tube has a small hole and if super glue clogs it, you are super screwed.
Silicon is something that you can remove if necessary.