Sound Historical Reasoning about Marco Polo

My sister, in an exchange with my inventive nephew, who is eight:

Da Neice asked why the call and response game was called "Marco Polo." I
was about to answer ("I don't know,") when Da Nephew jumped in.

"It's because when they were exploring North America -- "

"China!" I said.

"I mean, Africa -- "

"China!!" I said.

"They had an Indian guide -- "

"Seriously, you're thinking of Lewis and Clark!" I said.

"They would get separated and Polo would yell 'Marco' and Marco would
yell 'Polo,' and then they could find each other," he finished
confidently.

"You make me crazy," I said.