It is a bug. They should fix it. But that said, you can trivially change that DPI value in Photoshop or whatever graphics software you want without re-rendering or changing the pixel dimensions you are rendering it. E.g. https://helpx.adobe.com/photoshop/using/image-size-resolution.html

I'm more concerned about the difference in detail, which is an entirely separate issue. If you haven't already submitted those images to support, I think it's worth doing so and have them look at what's going on.