You could describe the specific "Old Tongue" alphabet and create a logic puzzle for the characters to solve to reach the pedestal.

KANE(Drawing a machete)I don’t like warnings that hum, Elara. Where’s the gold?

A rugged survivalist and Elara’s reluctant partner. He’s here for the payday, not the "cultural significance."

Perhaps the box is empty, and the "Treasure" is actually a map carved into the ceiling that only appears when their flashlights die.