The advisor and student may have in mind some particular specialization within the Ethnology tent. There are quite a number of schools that would allow an ethnological degree, some of them quite good. When I started looking for a place for specialized study, I picked one that had a staff member who could offer what I wanted. Luckily, I was able to get a teaching assistantship there.
Some schools like to have a graduate group with diverse backgrounds; I remember at mine that in my specialty there was always one spot (at least) for a qualified student from the British Isles. This was an inland state university.
Some schools have received large private scholarship funds from an individual or concern with certain restrictions on the type of student who is eligible. Again, the advisor may know of that kind of fund at the schools he recommended.
For these reasons, recommendations to other schools may not help.