As a former GM dealer…
As a former GM dealer service tech, shop Forman, service advisor and service manager I can tell you that a serpentine belt at 5000 miles is covered under warranty. The owner should call Chevrolet customer service and get his money back. The 1st point that warranty starts to not cover things is 6 months/7500 miles- that is for alignment, tire balance, key fob batteries and wiper blades. I just had a serpentine belt replaced on my 2023 Silverado diesel at 27,000 miles for noise. Coincidentally this was in Florida.