How do you get to the secret dig site in fossil fighters

there are two i think 1 is the ancient ruins :get Tarbo and T-rex rank 12 fight Rosie with them and go see Dr.Diggins. 2 is the underground mole cave: after chapter 8 you go to Rivet Ravine and go into Cave tunnel four then when you find a spot that goes four directions with a VMM go up then left use th ladder to go into the cave where you can find Brachio, Tricera, Nodo, Zino, Megath, and Chelon. Hope This Helps!