Heard on Memory alpha that an earlier draft, had Kira along for the ride, instead of nog, but Their was no way the authors could see Kira NOT laughing off, the "Field commisions" and taking command, or winding up stunned then thrown in the brig.
A lot think that "Captain Watter's" Was just not eager to return to being a Cadet.
Note in the Final bit on DS9
It shows Nog Having been promoted to lieutnenant junior grade.
NOT "Your Field commision is hereby terminated, for what its worth you fufilled your dutys exemplary, its time to report back to the academy to finish your classes.
Maybe he can cover 2 or 3 advanced senior classes with the bajoran mlitary academy.