It is remotely possible for a metal pin to get twisted enough that it can fall out of a socket, though you are the first to have this problem as far as I can remember (and the octal sockets have been going into BH kits since the 90s). I would recommend looking around in the packaging to see if the socket pin is still with the hardware, but otherwise you can contact replacementparts(at)bottlehead(dot)com to request a replacement. Please include your personal information so we can look up your order.
-PB