Maybe the perp was stalking SG for sometime. He may even have had a job he purposely took to get inside NG's house. Hell, he could have even worked for a security company. Perp wanted to know everything about SG.. He was focused on everything SG, NBC, Instagram, every TV appearance. imo. Might have even installed cameras that he then knew how to evade and dismantle.. He forgot about the Nest or that it was no longer operable. IMO, the perp was not stupid. He has confounded the authorities and captured his prey. NOW, he has not received the ransom nor sufficient begging from SG and he is boxed in. IMO, he never really wanted the ransom. He is taunting SG.. In his mind, she has spurned him. JMO