We know for a fact that Lyle Laverty was directly involved in the Patterson-Gimlin film event as a witness to trace evidence at the site, was among the first people in the scene after the filming event, took photos of the footprints himself, was a government official at the time, and eventually rose through the ranks of government to a near cabinet level position:
http://jkagroup.com/about/lyle-laverty-bio.htm#
There are also indications that Laverty had his own sighting near Hyampom, and found a nest near the PG film site at Scorpion Creek/Lonesome Ridge.