I could be wrong but it looks like the city is going to win this one on a couple levels. He admited that his birthdate is wrong on the license. They could argue it's not his and he has no right to be armed. I am not familiar with this particular park, but if they hold public events their they could make that public gathering argument. If they don't get him on the gun or tresspass, is lying to the police a crime? He was carrying a fraudulent document and he knew it. I could be wrong about it and reading to much in to it, the fact that he is sueing the cops and guard and not the city says alot. The guard did not infringe on his rights, he was doing his job according to the law as he understood it.
Weapons: Bows and arrows, explosives, fireworks, slingshots, fishing spears or any device that discharges projectiles by any means is prohibited. Firearms must be unloaded, cased and stored, unless a person possesses a valid weapons-carry license for a firearm that is valid in Georgia. A person possessing a valid weapon-carry license to carry a firearm valid in this state may carry such firearm on Georgia State Parks and Historic Sites, except on sites where carrying such firearm is prohibited by federal law. Firearms except those that are unloaded, cased and stored are not permitted on sites that are leased, federal Army Corps of Engineers property, including:
Red Top Mountain.
It sounds like he should be sueing the city, some cities in Georgia do have these laws and they may be unconstitional.