Who is questioned in Chapter 27 due to their involvement with Jamey and why are they questioned?

In Chapter 27, Dr. Mainwaring is questioned by Alex and Milo. Dr. Mainwaring is interrogated about the effects of drugs on a person and how well they mimic Schizophrenia. Mainwaring is accused of poisoning Jamey, but denies the accusations and instead said he was fooled.