Dear Mr. Ewen,
I'm afraid that you've already guess the practical answer to your question. While some medical schools in India set aside seats for non residents, particularly American, (often to get US$), Vellore CMC does not.... Of the handful of "open competition" seats, the competition favors, in most cases, those students who come from the Indian educational system since some of the science courses in the Indian educational system at that level of education are not given in the USA. In addition, since the selection process can involve several visits to Vellore, applicants outside India have the added expense of either staying in India for several months or traveling back and forth. All told, while an American is not excluded from applying or denied the possibility of acceptance, the reality is that they rarely succeed in the selection process.