Patterson film's an isolated occurrence, regardless of how verifiable it is.

Cave/rock paintings, not sure which specific ones you're referring to, but places like Lascaux and Chauvet date back to periods of human history where we weren't the only hominids walking the planet (i.e. neanderthals).

My burden of proof is as comparatively light as a modern patterson film shot in 4K, at least one additional occurrence, but none have presented themselves.

Additionally, if we are capable of tracking endangered animals like tigers, rhinos, elephants etc. within areas consisting of hundreds or thousands of square kilometres, how on earth could we possibly miss Bigfoot? No creature is so elusive that we could only have had meaningful encounters with one on one occasion in 1967.