The goat for Azazel does not of course atone for the specific sin of the 2 angels, Uza and Azazel, but rather it atones for the same sort of sin that they committed - namely Arayos. Their sin was that they "saw the daughters of the men" when they came down to the world. Rashi DH Uza explains that this teaches us that the goat for Azazel is a Kaparah for the sin of forbidden relations committed by Klal Yisrael all year round.

This is what the Gemara means when it says "Ma'aseh Uza v'Azazel" - their act, or according to the text of Ein Ya'akov (cited by Masores ha'Shas) "Avon Uza v'Azazel" - their sin. The goat on Yom Kipur atones for the same sin that they did.

The Gevuros Ari asks from the Mishnah (Shevuos 2b and Gemara there 12b) that the goat of Yom Kipur atones for all the sins of the Torah - so why does the Gemara imply that it only gives a Kaparah for Arayos? The Yad David (cited by Hebrew Artscrolls) answers that the Chidush of Tana d'Be Rebbi Yishmael is that the "Se'ir" atones even for Arayos, which are severe sins, and certainly atones for lighter sins.

A Guten Chodesh

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