PC 245(a)(1) reads: "Any person who commits an assault upon the person of another with a deadly weapon or instrument other than a firearm shall be punished by imprisonment in the state prison for two, three, or four years, or in a county jail for not exceeding one year, or by a fine not exceeding ten thousand dollars ($10,000), or by both the fine and imprisonment."
If the NFL wants to get serious they should have him charged. But that will never happen.
He should be charged - but I don't think the NFL gets a say. I think Mason Rudolph would have to go to the authorities and formally report the crime and request that charges be brought.