The world-building doesn't seem well thought out, regarding the discrimination against twins. All that fuss about twins could have been easily resolved by separating and raising them in different countries or continents. Nobody would know that the individual is a twin.
Or at least just change their features, hair color, etc. Or even just stop them from hugging each other all the time! 😄 If another party member takes one twin away to a different street/inn/etc., it's considerably less likely for them to be identified as twins.
But nobody thought of something so simple. Because plot. 💩 It's just silly.