I know alot of escorts out there don't drive, but how do you feel about a wg asking if she can have the money so she can take to her driver who is waiting outside in the car? Would you let her do it?
If she is intent on doing it. Nobody could stop her. But it will mean she is a scammer. Thus if she is a scammer she has no intentions of going through with the booking I think it's possibly best to just let her leave. But make sure you take a note of the licence plate number of the car she drives off in.
But if she just throws it up as a "can I" question. Think of it this way, if by some infinitely small chance she is on the level. It would take her at least 5mins to go and do this which is coming off your paid hour as she won't stay back she will be gone 60mins on the dot.