If Lu Chuan's guess is correct—meaning the sleepwear Zhang Mengyao was wearing did in fact belong to her—then it leads to the following inference.
The crime scene was very likely this very apartment.
Because there's no way Zhang Mengyao would have taken a set of sleepwear with her to work, then put it on at the moment she was killed.
So logically speaking, this sleepwear should have always been in Zhang Mengyao's wardrobe. The fact that she was wearing it at the time of death indicates she must have been killed here.
But this inference conflicts with the circumstances established by the investigation back when Zhang Mengyao disappeared. At that time, she definitely did not return home—that much is certain. The residential compound already had surveillance cameras back then.
The case file from that year clearly recorded the relevant query results: when Zhang Mengyao went missing, she never appeared on the compound's surveillance footage.
