I saw that press release but I have no idea how much silver usage would be required in the catalyst.
Somewhere between 4-5 mil oz/ year of platinum is used for auto catalytic converters so if that same amount were required it wouldn't really make a profound effect on the demand side considering metal has some negative demand impacts from the growth of digital photography but I am guessing it may require 4-5 times more silver than the Pt catalyst based on molecular weights.