I'm sharing this as a "Happened to a friend of mine" story. She was "kidnapped" by a stalker when she left work, he took her to his house and kept her tied up, then released her several days later, unharmed. I don't think he knew what he wanted to do with her, just wanted her. LE said nothing for weeks. The guy had skedaddled and my friend was terrified he would come and get her again. There was likely not any danger to anyone else as he seemed obsessed with her. The plan was to get him to calm down and think he was "safe" until they could track him(this was back in the early 80s, so no cameras and such). And that is exactly what happened, they tracked him with an atm withdrawal. Just some guy she knew from school, obsessed, mental health issues. Leading up he had left roses on her car, stuffed animals, other things like that.
Not saying that happened here, just that weird things do happen.