I was in the navy and did the same thing with some submarine technology against surface ships and they had no idea we were testing. Happens all the time. Sometimes they tell the captain. Sometimes they don’t. Depends on what response you want from the target.

I would assume from the video that anyone with a brain and night vision goggles on that crew also immediately put two and two together and figured out it was friendly, or they would have shot it down.

Really think a destroyer is gonna let an IR strobing enemy drone circle it for hours? If it’s not friendly, you assume it’s Chinese, not aliens.