One of the more compelling points about the Patterson-Gimlin film is Patty's proportions. Her legs are 1/3 her height. Not so on a human. I am 5'8" tall and if I had her proportions with leg length to height, I'd be 8 feet tall.
Her height is not so unusual if you consider one compelling aspect -
Human bones generally go through adolescence growing the forearm length and calf length first, then upper thigh, upper arm and the last growth takes place in the spine. Should her kind have a protracted adolescence, the spine would continue to grow.
Just a thought.