I hope your wife doesn't smell ammonia but just good cheese!
Kathrin, when you wash cheese its a lot easier to prevent foreign things from growing because you keep washing it over and over again, knocking down whatever contaminants are attempting to take hold. By the time you stop washing you have such overwhelming majority of your desired flora that it's difficult for contaminants to compete. And then of course, there is a matter of using good sanitizing practices: The wash bottle should be sanitized, the wash cloth should be sanitized, so is the box and the boards, and everything needs to be away from contaminants, trash, baking, pickling, meat curing etc.
Re wrapping, I forgot earlier to add this video. Slow it down. this is how you wrap a cheese such as this. If you can't get it right, head over to a good cheese shop and make friends with the cheesemonger. They do this all day long...