nobody is missing, because Kanda was the puppet so the guy with the helmet and everyone else got their belongings returned to them....I made the same mistake at first.
Sorry for the spoiler...don't read this without reading the manga first
Spoiler alert but kanda's face was actually the guy with the helmet's because kanda was made from 'parts' so when he died it was all returned to them
Ohhh I see, thanks!
Wait, since everyone meet up at the restaurant there was one person missing. I kinda wanted to see what he looks like without the helmet. D: