The problem with this is other people; the people she will have to work with, teach, speak to, and answer to various random questions during said tour. There is a very social connection between guide and tourist. What happens when she is nervous and stumbles over her words, or gives out the wrong information and gets corrected by a tourist, or when a tourist knows more than she does, or asks a question she doesn't know the answer to? I have done this kind of work when I was younger and you really need to focus on studying up, constantly, on the historic period, the area, the person, place, environ, everything, and know it inside out. You have to be able to speak clearly and loudly enough without a mic, and really present yourself, neatly and with decorum. You will have people from all over the world coming to your tours and need to prepare for the know-it-alls that will be dispersed in the tours, as well. And yes, you also have to be able to drive back and forth to your place of employment, rush through lunch, stand on your feet all day, and preferably not speak with your hands, but rather with your intelligence. Something she is highly lacking in. Her problems with anxiety and social gatherings would completely hinder her from being able to execute this kind of job. I think talking constantly, in front of people, day after day, would exhaust her. Another reason why I also cannot imagine her in teaching, at any level.