Everyone is overthinking this poem, think like a old explorer seeing land for the first time. go on a hike. I do not think he is lying about the hunt, he wants people to spend time outside, yes, who wouldn't. He want s a true explorer of nature to stumble upon it when he/she is taking in the immense beauty of nature. He is rich and his family is well taken care of, book sales are book sales, he says someone can find the treasure just by the poem alone, the book just gives you ideas on where he has been and ventured. Think outside the box and you may find the box..
"home of Brown"-could be a mixture of colors yellow+red=brown. hot springs create a yellow red look to them. just a thought.
"And take it in the canyon down" maybe a goose canyon? near a lake? goose lake near some hot springs...
"heavy loads and water high"- there are all kinds of huge boulders in creek beds in yellowstone, as well as many waterfalls.
"no paddle up your creek"- small creek, with pools.
"no place for the meek"- hot springs and geysers are loud and noisy, bubbling hot water and loud gushes of water.
I go to yellowstone for the beauty, now I have a even better reason to drag the wifey out and go to better hikes. Even if I dont find the treasure I hope someone does. This guy had a father that hid camping gear every winter in yellowstone only to return to have it untouched. just a note on ending this post, on his interview he stumbled and and almost said higher than 7000 feet. old people stumble one words of truth. maybe he was thinking of the treasure and almost said 7000 then corrected and said 5000. my two cents.