Reading about his life it doesn't say he thought he was in China.
Nicolet became the French ambassador to the Ho-Chunk people. He wore brightly colored robes and carried two pistols, to convey his authority. The Ho-Chunk people appreciated his ritual display. With some Ho-Chunk guides, Nicolet ascended the Fox River, portaged to the Wisconsin, and travelled down it until it began to widen. So sure, was he that he was near the ocean, that he stopped and went back to Quebec to report his discovery of a passage to the "South Sea," unaware that he had just missed finding the upper Mississippi River.
So I think the text above the image is completely made up.
Nicolet is noted for being the first European to explore Lake Michigan. In 1634 he became the first European to explore what would become Wisconsin. Jean Nicolet landed at Red Banks, near modern-day Green Bay, Wisconsin, in search of a passage to the Orient.[5] He and other French explorers had learned from their native contacts that the people who lived along these shores were called Ho-Chunk, which some French mistakenly translated as "People of the Sea".[6] In the Ho Chunk language, it means people of the big voice, because they believe their language was the original language of their family of tribal languages. However, the Ojibwe had a less appealing name for them, Winnebago, or "people of the fragrant waters," translated to French as, Puants or Puans. This exonym was derogatory, however, not knowing that, Nicolet concluded that the people must be from or near the Pacific Ocean and would provide a direct contact with China.[7]
"Thinking he was amongst a Chinese-affiliated culture along the route to China" would be more accurate than "Thinking he was in China", it would seem.
Reading about his life it doesn't say he thought he was in China.
https://en.m.wikipedia.org/wiki/Jean_Nicolet
So I think the text above the image is completely made up.
"Thinking he was amongst a Chinese-affiliated culture along the route to China" would be more accurate than "Thinking he was in China", it would seem.