If she would admit that's what it is, we could deal with that. Heck, I'd be a whole lot more inclined to giving up the endeavour for awhile and working it out. Instead, she'll only say it's 'cause they are nasty, smell, disgusting things. She's obviously not been anywhere near them. Even one of her very close friends who has had chickens has told her I'm right about them being minimal work, minimal fuss and minimal smell.
So far, I've told her she doesn't have to do anything with them. They are my project, but I've been trying to communicate and be open about them. That was the entire point about going out today. She has it stuck in her mind that Mama Hen cleaned everything up really well and gave the chickens a bath before the girls and I went over, just to make it look good. We argued about it for a good half hour tonight and she used the same four-word excuse the entire time. She can't come up with any real or productive reasons against it. Anyway, we'll keep trying. There's a few months before ordering starts in October.
Obviously, she believes what she is saying. You might want to find out WHY she says they're nasty, smelly, disgusting things, without trying to convince her otherwise. Could be she has been around chickens and that was her experience. Arguing with her experience (or the experience of someone close to her, like maybe her mother) is just asking for trouble. Recognizing and accepting her experience without judging it gives you a basis for finding a mutually acceptable course of action. Which might involve not getting chickens.

Regarding stinky chickens, the "Fermenting Feed for Meat Birds" thread made me think about your wife's reaction. Apparently meat chicken poo tends to be much smellier than layer chicken poo, and meat chickens confined to a pen are smelliest of all. Even the die-hard chicken lovers on that thread use words like "stinky" and "gagging" and "eyewatering" to describe the smell of broiler poop in a confined space. And they're only talking about 20-50 birds, not a large chicken farm. Those who have switched to fermented feed have reported that the "stink" level of their meat chickens has been much reduced since switching to fermented feeds. So, it made me wonder if your wife had at some point encountered a batch of meat chickens that WERE nasty, smelly and disgusting because of the way they were being kept. It can happen. If my first chicken encounter involved a batch of stinky chickens I wouldn't want anything to do with them. Just saying.
Good luck. I hope you work it out and can get some friendly, non-smelly chickens soon!