I never heard about four years until around two weeks ago. He wasn't that specific, he wanted more than two. It was never really established that we had a three-year offer on the table, it's just been some assumption originally cited by Ladson that everyone else has been quoting.
I don't think it is at all completely clear that four years was non-negotiable.
The 4 years was negotiable, but the Nats couldn't match the 3/57 offer that Dunn got from another team.