After they already went to all the trouble of making it as thin as they thought they could get away with?Yah, I would replace it if I had a spare cook box too. BUt that looks to be a very good fix. Weber might take note and maybe make that section of cookbox slightly thicker.
The damage on my Genesis ii happened before assembly so I'm guessing shipping damage.I am with Larry and admire the effort. I think even a little gray paint and maybe filler to cover the screws would go a long way. Better as is, than throwing away a $900 grill.
Although this happens to some old Genesis grills, this does seem to underscore just how thin the newer fireboxes are.