I know we can't expect any logic in TV shows these days, but Divya got 2 chances to overpower Sachini, first in temple where she was crushed under pillars and second when the gang knocked Sachini off.. She was motionless and unconscious for a large time. Infact initially she was lying on floor, why no one even tried or thought of snatching the ratnas from her pendent? They could have easily won over Sachini then.