In God of War, Kratos explores Pandora's Temple in search of Pandora's Box. At one point he enters the Chamber of Atlas, which houses the massive Statue of Atlas holding a model of the earth on its shoulders. By making the statue stand up and throw the globe on its back, Kratos is able to escape the room. Unlike the real Atlas, a giant four armed Titan with stone-like skin, this statue resembles a human. This may indicate that Pathos Verdes III did not know what the real Atlas looked like. The theory is most likely due to the fact that Atlas was imprisoned during the Titanomachy, which occurred long before Pathos was even born. The Gods most likely did not tell Pathos the real form of Atlas, probably because they did not think he was worthy of being portrayed in a statue.
Also, Atlas carried the world only after Kratos' fight with Persephone (a long time after the temple was built). Until then, he was just enchained to Tartarus. It is possible that Pathos could foresee the future and know that someday Kratos would have him enchained to hold the world.
Any pictures/carvings of Atlas found throughout the Challenge of Atlas also resemble the statue.