I've always personally maintained that Hicks was Fox's escape plan for Alien 4. (One they didn't use, obviously.)
Hear me out now...the opening montage shows the egg, a facehugger, a scan of someone being hugged. We know it's not Newt...it's Ripley, right?
Then what is that shot in the montage of white cloth being soaked in blood along with an Alien screech? Sure as hell seems to indicate someone giving birth to an Alien. If not not, then what?
My theory is a facehugger for Hicks, which births and stays on the ship. One live Alien, on board the Sulaco, headed back to Earth. The EEV is launched and crashes, and a support beam goes through Hicks, destroying any evidence that a chestburst took place.
Crazy? Maybe, but no worse than some theories bandied around in these here parts.