What is meant by Global-warming Potential (GWP)?
Rather than using the GWP as a ratio, they are expressing the GWP as compared to a release of $\ce{CO2}$ with equivalent radiative effects.  To use their numbers use the mass they give you and a GWP ratio of 1 for that mass (as if it were carbon dioxide).  From what I've seen for chemical industry sales and marketing literature it is fairly common that they express GWP this way in units of "$\ce{CO2}$ equivalent".

In other words, they are saying whatever their product is made of and its production methods have the same radiative forcing as $x$ kg of $\ce{CO2}$.