Finding Ryokai at home could have been luck, but finding Machiko at her parent's home, rather than at her own condo, that hints at more than mere luck. It would take planning. Perhaps even the support of a skilled decker. The Nagato Manor Residence Community where Machiko's parents live is Nagato-owned, but operated and secured by a subsidiary, and that subsidiary maintains a complete security establishment. A skilled decker with experience at sleazing information from computers could have breached the Residence Community's computer system and determined that Machiko had been cleared through the Community's main entrance earlier in the evening.