DNA does not degrade all that fast in the wild and I have found deer skeletons and in one case a bear skull in the wild, all of which would have had viable DNA. A den would contain DNA, feces, hair, and skin should be present in a den. Even you tube hits make money, money is being made or attempted to be made on this. But even that aside, fame is enough of a motive and for some fooling the experts is more than enough motive, look at the millions of fake UFO videos on you tube.
This will eventually shake out, I would love it if bigfoot was real but not enough to accept horse feathers a proof...