Here’s a link to some information about moving on to Emory’s business school after Oxford College:
http://oxford.emory.edu/academics/student-services/pre-professional-advising/pre-business-information/
As you can see, being able to take all the prerequisites at Oxford in your two years there will not be a problem.
The business school admissions process is competitive for both Oxford and Emory main campus continuees. I’m not sure about admissions rates from Oxford applicants. You can probably ask the Oxford admissions office or the business school admissions office for this kind of information.
The education you would get at Oxford College is excellent. The class sizes are small and there is an emphasis on teaching on the Oxford College campus.
If you intend to compete for competitive jobs after college (management consulting, investment banking, private equity, etc.), then the prestige of your undergraduate program will matter. The same is true if you intend to apply to a competitive MBA program somewhere down the road.
Have you asked Oxford to increase your aid and/or give you a better mix of grants v. loans?