That's always been a problem for me when considering the PGF a hoax. As Norse says, Gimlin would have had to been in on the hoax so that Roger would know for sure he wasn't going to shoot.
They agreed ahead of time, don't shoot one unless it charges. Maybe Roger thought he knew Bob well enough that he would stick to his word, but that's still taking a heck of a chance.
So unless Roger was playing with someone wearing a suit's life, Bob would have to be in on the hoax. But that raises the question why Bob didn't bust the hoax after he became so angry at Roger that they didn't speak again until Roger was on his death bed.
I've always had a hard time squaring that, even though I'm inclined to think it is a hoax.
Well, if it's the real deal, I've always thought Patty showed basic motherly instinct to lead a threat away from the direction of her young. It's not that she wasn't worried, she was just willing to risk her life to save her young.