I don't know about anyone making it through the entire war without hearing about it, but there are some instances of people kinda making it partway.

One of the more famous examples, Shackleton left on his disastrous Antarctic expedition the same month as the war began in Fall 1914. When he returned to civilization in Spring 1917, one of the first things he asked about was when the war ended.

From South!, Shackleton's personal account;

"Tell me, when was the war over?" I asked.

"The war is not over," he answered. "Millions are being killed. Europe is mad. The world is mad."

So if nothing else, being shipwrecked on Antarctic sea ice was enough to insulate you from the news!

One place that would not have heard about WWI as it was happening was the highlands of New Guinea. This region wasn't visited by Westerners until the 1930s, and in fact the West wasn't aware it was even inhabited until airplane flyovers in the '20s revealed the dense human settlements there.

There were also still many cultural groups in the inner parts of South America that had had only limited contact or none at all with the west.