When a question migrates, answers are deleted and the question left as a stub. For example, a question is migrated from site superuser (post id: 82342) to stack overflow (post id: 1894170). I can access the edit history of 82342 (https://superuser.com/posts/82342/revisions), but my question: is it possible to collect that information from any data dump? The stack exchange data dump (PostHistory) does not contain any information about the deleted post (I have seen PostsWithDeleted in SEDE but that does not contain history).
Content of posts which are outright deleted can't be accessed through SEDE; you'll need other tricks to download them altogether, like an Apple Script.
It looks like that upon migration a question, only the final version of a post is migrated, so there is no way to get the complete history from SEDE.