Hm
It seems that if you move the crystal in the carvings it activates the trap.

Control: Party
Exit room to Aligator room.
Control: Araches
Enter: Pedistal room
Grab: Orb
Rejoin with party.
Give: Orb: Fawriel
Enter: Pedistal room
Cast: Haste: Araches
Grab Crystal
Exit room.
Control: Fawriel
Cast: Town Pipe: Trading post