actually that still is from the patterson film, which remains the best 'evidence' as of yet, as it has never been disproven and no one has been able to recreate it. it was shot in the 1960's and modern day image enhancement shows moving muscle under the skin. who knows if theres any truth to this stuff but as for what is in that film, it has yet to be debunked.
as for the 'man in the suit' coming forward, there have been literally dozens of men claiming to be the 'guy in the suit' so that alone makes each claim highly suspect. the men who shot the original film in the 60's are already dead.