Flex has nothing to do it.
The values posted on Völkl's website, as well as all other manufacturer's sites, are sidecut radii. In short, they are an approximation of the radius of the cirlce from which the skis sidecut was derived. Keeping in mind, of course, that this is only an approximation because there are virtually no circular radius skis out there any more. Most are elliptical, some are still parabolic, and a few are dual-radius circular.
As for the Karma specifically, I think the values posted for the 05/06 ski seem more believable.
There is a formula to figure out the radius, but you need to know the distance between the widest part of the tip and the widest part of the tail, and you couldn't know that without having a ski in your posession.