Well, the way I see it you made a smart choice.
My (ex) wife did some amateur modeling and this really creepy guy offered to pay her for some work. While she had been paid in the past it was almost always in the form of product, it was very strange to offer cash for non nude photography and he didn't have any product he was pushing he merely wanted "work for his portfolio"...
Well she said sure, but I have to get two of my friends to come along And the shots have to be at the beach (he lived near the beach) and he had to pay our expenses down there. So I went with he being careful to stay armed and not eat or drink anything this guy would offer, while she did the shoot. The only weird thing was he wanted some shots of us together, nothing nude or even suggestive but very weird the way he went about it.
Turns out he just wanted some black girls (my ex was black) on his portfolio and he didn't actually know a single black person, but knew that his portfolio would be taken more seriously if it were ethnically diverse
While this person turned out to not be as dangerous as we thought, he very well could have been. If you ever deal with someone sketchy never go alone, always remain vigilant, and always remain in control. If that person insists on doing anything in private just leave. Nothing is worth you safety or your life.