There were blond haired, blue eyed guys who could not speak a word of Spanish walking around on Chilean Bases. Now the British were the third largest group of emigrants to Chile but most of them spoke Spanish by that time.
It was a major goof by Argentina to reveal their plans but they were doing a "wag the dog" to divert attention from the fact their leaders were incompetents.
Yep, they bought some time with hosting and winning the World Cup in 1978, but eventually that wore off.