Nitter should have anticipated this and planned accordingly. The law is the law. Njalla is a wonderful service but they are not outlaws. They are structured in such a way to make it more difficult to stop their customers, and they hold less data about them. But they operate within the law.
If you use their service and don’t take the adequate steps to protect your privacy, they will give away your data in accordance with the laws of the domicile they operate under.