I just want to say that you seem like a great person and you are eager to make your wife happy. It definitely seems like it’s not the actual cleaning help that’s troubling you but the underlying middos/ perspective/ mentality of your wife.
I’m sorry I don’t have any advice for you (well, maybe some, but I’m not giving any) I just wanted to commend you for trying to understand her and I hope that the two of you have many happy, loving, understanding, special years together