first of all, professors do not know much about medical school admissions. People without greencard and citizenship do get accepted if they have the grades and money to pay for 4 year worth of school. but mostly if someone is illegal, they do not have 200k in the bank to show to the school and that will be the reason for the rejection. But honestly speaking, I am not sure how many people here are even academically prepared to even apply for medical school. do not think about your status first, get your MCAT and GPA grades first and worry about them later.