I have to agree that the role of the college ambassador has been very well defined thus far. A person in this role works with both the university/college. the current students, and the potential students of the school. This person needs to be friendly, well spoken, and understand the concerns and fears of both the school and the students. Therefore, the college ambassador fits the "been there, done that" persona so that they can speak from experience and ease fears.
Yes, a campus ambassador normally is responsible for acting as an ambassador for his or her college. This is a role that involves direct contact with potential students and their families and giving tours of the campus so that others can see the campus for themselves and consider whether they would want to go there.
In my job as a campus ambassador, I worked under the direction of the Director of Admissions. I gave tours of the campus to prospective students and their parents and answered questions, with the hope (of course) that having a chance to talk to an actual student and see the school from a student's perspective awould be less intimidating and more informative than talking to an adult in an office.
A campus ambassador might be someone from a college or university whose job it is to visit various high schools and talk about the school. Being a member of the college community, they would be able to speak to all areas of campus life from a student's perspective including their own personal experiences. Sometimes this kind of information is more valuable to perspective students than what the school's administrators can speak to. A student who is working as an ambassador should have an outgoing personality and project a positive attitude about the school and the kinds of students who choose to attend there.
At many colleges, a "campus ambassador" is a student chosen to represent the school in meeting and greeting visitors to the campus, especially potential students and their parents. Camus ambassadors are usually very good students who are articulate and friendly and who can explain, with genuine enthusiasm, the attractions of the school.