OH! Hi! I can post now. I'm new, and I'm a little bit nervous to jump in so go easy on me. I've been reading these forums for a long time but just registered for the first time.
A couple of theories from reading this entire thread (and the two prior ones).
People keep asking why WG would know she was distressed when he was in front of her. As someone who was once a young college girl, being followed by what looks to be a group of young men, there could have been an exchange going on there. Some cat-calling type stuff. WG could have heard what was going on, stopped, then deliberately inserted himself between the group of young men and Hannah as a safety measure.
As an older gentleman, if you put yourself in his shoes, it may have been prudent not to approach a young 18 year old alone. He may have thought- better to follow and make sure she gets where she's going than to stop her and freak her out even more.
I have no idea why he would then let her walk off with another man, unless she acted like she knew him and he assumed this is where she was walking so purposefully.
I also just want to say, as a woman... If I see a young girl looking disoriented late at night, I usually either keep an eye out for her or flat out ask her if she needs help. I did this many times even in college. It hurts my heart to see so many innocent, probably kind strangers she passes and not one seems to be concerned. Take care of each other!!!
All of this is just my opinion and as I said I'm new so go easy on me!