Good point.
I had ignored leg color on those two, because I figured either one could have a variety of leg colors. But now that you mention it I went and checked their website, and McMurray does say "mixed" leg color for the Whiting True Blue and "green" for the Ameraucana. So you are probably right about which chick is supposed to be each kind.
(If McMurray's "Ameraucanas" have green legs, that is actually wrong according to the standards of the American Poultry Association, but McMurray obviously isn't too concerned about meeting the APA standards here.)