Hello!! Omg sorry this is so late! It's been a few years but I believe every item has to be used to complete the game. Try talking to grays that didn't do anything before, like the one walking around the plant. Hope that helps!!
I got stuck at the egg for a long time, too. So for the benefit of any future travelers who find themselves in the same situation, here's what you gotta do:
Talk to the rude guy next to the bookcases, specifically while you have both the egg and at least $10 saved up in your inventory.
