Jeff,
Do you still have the rest of the A0 paper you cut the templates from ? If so, check the verification dimensions on the edge of the paper for discrepancies.
You are looking for fractional differences, don't stress if you come across a couple that are a whole inch out as Jon had a couple of dyslexic moments when he was adding the verification dimensions.
Sorry, I think you are asking how to prove the templates if the verification dimensions are not available ? I guess the only other option is to compare chord line dimensions. Which of your templates do you not have the verification dimensions available for? I am sure somebody can run a ruler over their prints.
Pete