It is reasonably hard to get into Vanderbilt and by no means guaranteed. Some have attended Vanderbilt free of cost with some full scholarships.
I am aware of two students who had large merit scholarships at Vanderbilt who graduated this year and are enrolled in a prestigious medical school with partial scholarships.
Good students should not be dissuaded from trying to get into schools which provide financial aid and/or merit scholarships with awareness that they should save money for med schools and not spend on undergrad.
Ultimately it comes down to how well they do at any school they attend and whether they are doing “all” it takes to create a great med school app.