Has anyone suffered major kidney damage through an infection?

Yes: A severe blood infection can cause damage to multiple organs including the kidney. The kidney damage is often caused by low blood pressure, and is typically temporary and improves after the infection is treated. But with severe infection, or prolonged low blood pressure, subsequent damage to the kidney may be permanent, or severe, requiring dialysis.

Yes,: Besides acute sepsis causing acute kidney injury, chronic untreated longstanding kidney infections can ruin the organ and sometimes it has to be removed by the urologist (like in cases called pyonephrosis). It is wise to treat infections promptly.