
Continuity mistake: Just before the diner scene, where the two aliens are discussing the galaxy, we see the outside of the Russian restaurant. The neon sign says "haroshaya" meaning "good" all the way across the window, in the next shot inside the restaurant, the "ha", which looks like the English letters "xo", is gone and the sign is centered. (00:41:00)
Answer: The person in question is actor/comedian David Cross. In the first MIB film, Cross is listed in the credits as "Morgue Attendant," and he ends up glued to the morgue ceiling, presumably killed by The Bug. If he had survived, the Men in Black would have certainly neuralized him, anyway, and he would have no memory of the alien encounter or the Men in Black. In MIB 2, David Cross is listed as "Newton" (the video store nerd) who apparently recognizes K, because K had asked Newton to reserve a videotape for him at some time in the past. K made this video request before he ever met J, and then K neuralized himself after leaving a trail of clues leading to the video store. Newton remembers K, so Newton hasn't been neuralized in years. Therefore, Newton in MIB2 cannot be the same character as the Morgue Attendant in MIB.
Jazetopher