A JW would have asked her if she needed help, then he would have counted the
time preaching to her because he mentioned Jehovah or the Bible once during
the conversation.
She had a phone and was able to get help. I know what you mean, though.
Do I get involved or not- will she think I am a creep or not, WWJD (kidding).
I would say if you didn't see the phone, or there wasn't a place nearby or
if it was late, or ...- then you could offer to help. You did fine.