The Americas stayed ‘discovered’ at least as long ago as the 11th century...
You miss the point about “Discovered”.
As far as I know the first written accounts come from Chris.
No other kingdoms went in search of the place until then.
Nor did any Puritans...
Apparently you have an odd definition of “discovered”. The Vikings are and were known to have settlements in Iceland, Greenland, and the Americas. Like Clovis-First-and-Only, Columbus-first-and-only started to get enforced around a century ago. Prior to that time it was accepted and even taught that the Vikings made the trip and returned. Anecdotally, I’ve got one of those local history books (basically, people paid to have their family story published alongside bios of presidents and other well-known people) from about 1900, and the Leif Erickson story is right in the first chapter.
Columbus’ records have actually vanished, copies have survived which are generally in agreement with each other. The original of his first voyage log vanished into the archives, the oldest known copy vanished before 1600, and a summary was extracted from it before it did.
But Christopher Columbus went to Iceland to do research, because it was generally known that land lay across the ocean, and that the Vikings had been there. He purportedly figured that it must be China, and that the estimated circumference of the Earth passed down from the Greeks was in error. Had he been a scholar, he might have noticed a reference to the Americas in Plato’s dialogues.