Fatigue is different than extending.

If it wasn't, there wouldn't be an extention option; it would only be the max 100% of the time with fatigue as needed.

The extention option should be a Y/N question at the appropriate time and if the answer is N, that's it. Go to rest, no report, no explanation, no review board, nothing.

Pretending its a fatigue issue is asinine. Fatigue at exactly -2 hrs would be a total and complete coinsidence and since fatigue requires a call out whenever it happens (at hour 1, hour 15 or anywhere in between) then the -2 extention threshold has nothing whatsoever to do with fatigue.