Yes, Vitaminwater is a product of The Coca-Cola Company.
The Coca-Cola Company owns a diverse portfolio of beverage brands, and Vitaminwater is included among its hydration, sports, coffee, and tea brands. This means Coca-Cola is responsible for the production, distribution, and marketing of Vitaminwater.
Here's what the Coca-Cola Company stated in March 2023:
Our hydration, sports, coffee and tea brands include Dasani, smartwater, vitaminwater, Topo Chico, BODYARMOR, Powerade, Costa, Georgia, Gold Peak and Ayataka.
Therefore, Vitaminwater is indeed a Coca-Cola product.