He won't even say it could have been a Bigfoot.
The teller was losing hope that there was anything to Bigfoot when they went moose hunting in Maine with their father, who had drawn a moose permit in the lottery. Their guide for the hunt was a nurse their father works with at the local emergency room, a man in his forties who has guided since he was twenty and spent his entire life in those woods. The teller had to ask whether he'd ever run into anything strange.
He said yes, once, about twenty years earlier. He made a point of saying first that he has never believed in the paranormal and wouldn't claim it was Bigfoot.
He had been guiding a bear hunt. The method is to set up bait barrels full of sweet treats and put each hunter in a tree stand within sight of a barrel. At the end of the day he set off on foot through the woods to pick up his hunter.
Halfway there, an enormous "WOOP!" rang out through the trees, followed by several more. In a whole life in those woods he had never heard anything like it, and he was terrified.
Then, as he kept walking, he could clearly hear footsteps following behind him. It was too dark to see anything. He walked with his pistol drawn. Then came a loud crash. He thinks it might have been something thrown, a log perhaps, or a dead tree being shoved over.
When he reached the stand, his hunter was shaking. The hunter had been hearing the whoops too, and for more than half an hour something had been walking around behind his stand before the guide arrived. Neither man stayed to find out what it was. They got out of there fast.
That's the whole story. He never saw a thing, and he still won't say what it was or whether it could have been a Bigfoot. The teller says he told it quietly and sincerely, even while the teller's father was cracking jokes, and that it convinced them more than any video ever had.
For what it's worth, the guide's territory is the same part of Maine where, in 1886, local newspapers reported a ten-foot "wild man" had been killed.