If that happened there would be no way the Nats pick up the fourth year.
Maybe so but at that point I don't think it would matter. That's 3 full years to find someone to replace the bat. But from Dunn's perspective, his and his agent would be fools to think the Lerners would pick up that option when they are reluctant to pay him now when he is still in his prime.
Besides, 3 years would be fine with me.