Chaos!

Their story on getting petrified so easily is actually justified.
Dunamis, that knight in Leafre was cursed by Eleonor. She justifies it'd be kinda obvious to invade the land with Black Mage subordinates, and that would cause knights to attack and defend the territory.
But once Dunamis stepped on the land, everyone turned into stone. Because they weren't even expecting such attack. It's not that they're weak as pomegranate. It's more likely because it was a surprise attack, and a curse coming from one of their knights, that wasn't also aware of what he turned into.

That seems very cop-out like.

I like my idea story better.