My problem with the Queen is that there's no way she snuck the egg on. That theory just needs to be dropped all together. She was chasing and fighting Ripley the entire time. She never crawled back to the cryo chambers and planted the egg and then crawled back under the dropship to surprise Ripley. And she definitely was not squeezing an egg between her legs as she chased Ripley up an elevator and off the planet and during a major battle.
As much comical fun as you could have with saying that the company snuck on and planted an egg while they were sleeping, it once again makes zero logical sense. Though the egg being onboard already makes zero logical sense. At that point you could just take control of the ship without diverting to Fury 161. Why waste the time? And if the company did sabotage the ship why would you divert it to another planet to being with? Why not divert it somewhere you can access the ship more quickly?
Now the ONE possibility I see here that makes sense is bishop. The problem is Bishops honesty throughout Aliens that makes this difficult to believe. He told them straight up about Burke, why would he have done that only to have hidden sabotaging the ship with an egg from them? And if he had done it I'm assuming it was done earlier in the film where he had time, but that means he probably would have confessed as he did when he told them Burke told him to keep the face huggers alive. HOWEVER, if you really want to make some lazy writing which is all Alien 3 and Alien R is, you can just say Bishop was forced to bring a egg onboard by Burke while the others were distracted. Bishop could have remotely controlled the dropship, maybe an electrical cart to extract the egg, and hide it temporarily. But it would totally go against the character arc Bishop had throughout Aliens and a brief moment in A3.
I might get a lot of resistance for this take but I liked how Aliens Colonial Marines the video game had Hicks wake up, kill that guy, and throw him in his cryo tube. That storyline was cool and an easy fix for one of the characters. But I also think it only fits in the sense of like a comic book or in this case video game.