'Baking bread with dung' could conceivably be imagined to mean that the dung was the fuel for the fire, rather than an ingredient of the bread. I might point out that human dung probably doesn't burn very well, whereas the dung of herbivores would be a better fuel.
However, in order to do justice to the book of Ezekiel I will mention one of its other famous problems.
Much of chapter 26 is devoted to the devastation of the coastal city of Tyre. God seemed to be rather biassed against it and there is a long description about what he plans for the city. In fact, the destruction was not planned for some vague and generic time in the future. It was to be at the hands of Nebuchadnezzar, King of Babylon.
But it didn't happen! Tyre is still there and was never destroyed as the bible predicted.
Biblical infallibility is again shown to be wrong!