Might be PL-16. Only AAM to enter service without being spotted in the wild even once.
Knowing the PLA/CCTV, I wouldn't be surprised if it was nothing interesting and they're obscuring it because sometimes they're silly.
Putting it another way, just because something is obscured certainly shouldn't be taken as indication that it is done for a good reason lol
I remember one time i think they literally obscured the radome of a J-20 even though by that point there had been innumerable photos and videos of J-20s all over the place (radome included of course)