it doesn't make sense with the context of Aliens. Never will.
But it's not a plot hole "within" Alien3. It's the inciting incident, if you like that film you accept it as a story on its own.. and then move on from inconsistencies with the other films.
It reminds me of Hellraiser 2 which opens by blatantly retconning the whole climax of the first film and seems to exist as its own "alternate world" sequel.
(the house never blows up.. the boyfriend just doesn't exist.. etc.)