"Secondly, when the explorers got to the Americas, they found Chinese people there. "
I have never heard this. Any idea what he's talking about? And, where did they go?
Part III - Evidence of the Voyages of Zheng He Fleets:
http://www.1421.tv/pages/evidence/content.asp?EvidenceID=25
Chinese or Asiatic People found by the First European Explorers
http://www.1421.tv/pages/evidence/content.asp?EvidenceID=26
Local peoples descriptions of Chinese or Asiatic peoples who settled amongst them before Europeans arrived and descriptions of their ancestry
http://www.1421.tv/pages/evidence/content.asp?EvidenceID=27
Linguistics and Languages common to the New World and China
http://www.1421.tv/pages/evidence/index.asp?Section=9