Can my private university force me to buy its student health insurance?

I am currently covered by a state-enhanced version of Medicare; my family is extremely low-income and this health coverage is far superior to that offered by the private graduate school I will be attending this fall. However, the school is not accepting my waiver form saying that government insurance does not meet the school's waiver qualifications (only employer insurance programs do). Can they do this to me and make me pay thousands of dollars I don't have for redundant school health insurance I don't need? Anyone knowledgeable enough to know whether this is something I can fight legally? The school and my insurance are in NJ.
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A private school can require you to do just about anything as a condition of admittance -- because they are a private institution, not a govt agency. It's all a matter of contract -- you can either do what they want, or not accept admission. Your choice. Racial prejudice is about the only thing prohibited -- and that's only under the 13th Amendment, which affects private groups -- the 14th only applies to govt action.
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