Cullen is waiting for a call, he is wondering, there is no unusual call. It is impossible and peculiar for the kidnapper that they don't get pieces of information from their target and don't know any number to contact the family of the victim.
If Drake is being kidnapped by someone, what must be their purpose, why they aren't calling for ransom, or not even receiving any threat. He is really puzzled. At first, he doesn't want to ask, maybe they will panic if they learn that Drake is missing. Maybe Drake's family thought he slept over in his house so they don't bother to call or confirm if they go to school already.
Finally, Cullen decided to inform Sander's family since he knew Drake's location. He even asks for help from the police and gives Drake's location. That OX head necklace is a
