That scandal in the EU was not argentinian horse meat. It was domestic EU horse meat from Romania and Poland. And the whole fraud did not even originate in those countries, it was meat middle men in the Netherlands and France who relabeled, once correctly labeled horse meat, to beef. That's what makes this whole current rumor so implausible. Mislabeling horse as beef in the import stage would require the inspections both in Argentina and the entry inspection in the US to both fail. It would be far easier for something like this to happen inside the US by US companies than Argentina trying to commit a scam like this.