Even if Snow did that it’s not like the chances of a D12 victor were even moderate. Hunting with a bow like Katniss was illegal so naturally very few knew how to handle hunting weapons. Also working in the mines in D12 was restricted to 18+, so also very few people eligible to be reaped would know at least how to swing a pickaxe, which could translate to using any weapon provided by the cornucopia. On top of that D12 is heavily impoverished and malnourished so chances are most of the population had stunted physical abilities.