This is an issue I’ve noticed when using responsive imagery alongside grid elements. My guess is that even though the image is taking up multiple cells, it’s acting as though it’s just taking up one.
I haven’t tested this yet, but I believe adding a grid area may fix this issue. If that doesn’t work, given the simplicity of this element presentation, you can always swap out the grid element for a flex—or even a standard—div and it should display the appropriate image size.
Let me know if you run into any issues 