Rudie has the keys to escape from this infection but you have to do a quest for them, which is finding the cure, but you don’t know that because you have interacted with him yet but he is half infected. He is still a survivor trying to get out of here.

“Hey.. are you trying to come here so you can get the keys so you can escape not to be a betrayal to you but you have to do a quest for it which is getting the cure so I can cure everyone, but some aren’t easy so you gotta give me a syringe with it too”