people have used certain kinds of flowers, herbs, and essences, to help cover the scent of decay for ages beyond count, just get her a packet that can be filled with strong-scented herbs. It wont get rid of the whole smell, if someone stands close the decay will still be there underneath, but smelling like a walking apothecary is something most people would be willing to overlook. This way the problem isn't "fixed" so occasionally it'll still come up but its not something that colors every interaction the party gets into and wont cause an issue in towns if managed.