Hi juggler,
Looking at the videos, the day is very good and the night is grainy which is typical for many of the Ambarella A2S60 cameras (F900LHD, F500LHD, GS1000, etc.) The grainy video may appear disappointing but trust me there are much worse. Watching your video, it appears to be brightly lit and reading street signs is possible. Reading license plates seems a bit difficult though. Overall, the video seems reasonable.
For very good night video, you generally need a camera that costs $200+ (Itronics, BlackVue, FineVu, etc.).
To determine whether it is real or fake you need to check the firmware. I believe you mentioned your firmware was V2.29 BS-MF H. The "real" cameras have firmware ending with OTH-MF H. Even though yours is not the same as the DOD F900LHD, the quality is reasonable. I am curious where you purchased from?
Dash Cam Man