You have to understand though, that Tentsu, who is the corporation behind the E-Series apparently, is not a "terrorrist" as some of you are implying, but rather this world's equivalent of an arms dealer, and while it may be unethical to me or you, it's a pretty legal job in our world.
Imo Mia is not a terrible person, she seems to love Ethan and even though she lied, it was done to protect him.
I also don't think that Ethan didn't know anything. I mean in a grander scale. For example i'm sure he knew about Mia's work, about bioweapons, and maybe even worked in the field himself. He is seemingly not that shocked that things he witnesses exist, neither shocked Mia is tied to this situation. Even in the end, it seems that Redfield introduced himself as if expecting Ethan to realize he is safe just by hearing his name, like Ethan was aware of the situation.
I wouldn't be surprised if the story Paid DLC, or NaH, or a sequel shows that Ethan was familiar with bioweapons, even in a theoretical level, and by theoretical I don't mean having seen them on TV, i mean working in the field.