This^^^^^
Also, BC was done with his degree and was no longer associated with the Physics department when he committed (again, allegedly) this crime. In fact, the last semester in school, he wasn't even taking any physics classes. He was taking some electives and finishing his master's thesis, IIRC. Highly, highly unlikely he could have done anything to her on campus at some facility on a Friday evening. There are cameras at entries to these buildings, and many now have keycard access. Most university IDs are now also prox cards that can be programmed to let you into buildings you are granted access to as a student/faculty/staff member. They are eventually deactivated when you graduate or otherwise leave the university. BC had just graduated, so his card might have already been deactivated, but it is possible his student ID might still have been active allowing him access to places he had access to when he was a full-time student. However, I believe your use of your card to enter buildings is logged, and I'm sure that once investigators had him in their sights, they were looking at logs of building access between the 9th and the 12th to see if he attempted to enter places on campus -and they would be looking at security camera footage from any buildings he might have tried/succeeded at gaining access to. Additionally, if we presume that the timeframe mentioned in the Chinese article is correct (she was killed ~5 hours after being picked up), it would be hard to imagine him torturing/killing her in some lab facility. First, he would have to take her to some facility AFTER having her at his apartment against her will for a while (the criminal complaint clearly mentions she was taken to his apartment, and more info on this fact was revealed at his bond hearing on the 5th of July. The superseding indictment of October 3rd also alleges he had her at his apartment). Second, he would be on campus in a research facility around 5-7 PM. At that time in these research facilities, even in the summer on a Friday evening, it would not be uncommon to find grad students or other researchers still there doing work on experiments. They wouldn't be as busy as they would in the middle of the week on a weekday evening, sure, but the possibility would still be high that a few people might be around doing things. He would know this, and he wouldn't run the risk of taking her somewhere where someone could stumble across him doing these things, and thus witness him and potentially try to intercede to stop him.
Highly, highly doubtful he did anything to her on campus.
That said, I can think of a couple of facilities on campus where he might have been able to dispose of her -but I have no idea if he would know about them; and even if he did, I doubt he could gain access to them, or if he somehow did, would be able to operate the equipment necessary and not have someone on Monday morning realize that something unusual had happened over the weekend at the facility.......