They’ll test it for the weight, however it’s important to understand the testing cycle. Were the tests only setup on flat ground? Did they adequately test braking? Did they ride the brakes for a while?

Well, it seems that you are not familiar with European road safety testing and certification. My BIL was working in that area, and his executive summary of that was: if it passes European tests, you can sign the American test papers, too, as it would pass them with flying colors.