If conception of the invention or reduction thereof to practice (hereinafter: “to Invent” or “Invention” etc.) occurs before March 15, 2013, and did so before anyone else, one may obtain the patent even if one hasn't filed for a patent thereon at any time provided someone else did file for and obtained the patent who was not the first to Invent since the first to Invent is entitled to the patent. This may occur through, for e.g., a lawsuit, or civil agreement. This pre-March 16, 2013 era was governed by the “first-to-invent" principle.
However, any invention since March 16, 2013, the full force and effect of the America Invents Act, would not have such opportunity to sue or seek a settlement as the "first-to-invent" rule was changed to a "first-inventor-to-file" except in case of theft. Even under this principle, one theoretically could sue if the facts can be established that what happened for another to file earlier was the result of conversion or even criminal theft of notes or other documents including the invention to "obtain" the patent through criminal and/or civil prosecution.
Accordingly, scenario 2 if occurred since March 16, 2013 would, indeed apply, but it is advisable to be ready to defend the position that one was, in fact, an inventor (and not a "patent thief").