The "Last saved by" indication is always that of the default revision currently, not the revision affected by the translation being viewed.
User A creates a Dutch article, while User B translates that Dutch article to English.
When viewing the Dutch version of the article, User B is mentioned on "Last saved by" - while User B never touched the Dutch article. Here we expect User A to be mentioned, while User B should be mentioned on the English translation,
Patch #3 applies clearly for 2.0.0-beta1, tested and works as expected, code LGTM.