Yes, they are in there, because these religions are based on old buddhism and certain things remained. However, nobody cares about them as they are seen as useless rudiments, rather than real goals or at least variants of spiritual way.Do we find four stages of sainthood in Mahayana or Vajrayana?
They don't really care about that. Many of them even don't know about such a thing.Then how do they eliminate ten fetters?
Mahayana and Vajrayana teach how to become a Buddha (who is, well, more "a God" rather than "theravadin buddha"). And the way to become one is quite different, especially in Vajrayana with its tantras and so on.
Ancient mahayana texts are very close in doctrine and practice to theravadin texts, however, that was long long time ago (some 1500-2000 years ago). Since that Mahayana developed a lot and those old doctrinal parts and practices became rudiments. Just read some modern books about Mayahana and Vajrayana, and you'll see that.