This situation sucks, I totally understand. If you are forced to adhere to a shitty meal plan because of your class status or living situation, you might want to follow a course of action in which you move to a reduced debit plan, or all debit plan, or NO meal plan whatsoever - in which case you can simply go pick up your $2k-ish check from the Bursar.
I think you should first and foremost try to speak with people in a friendly manner at your Bursar's Office, or Student Financial Services, and explain that you have needs for better nutrition. If you mention hypoglycaemia or diabetes, you might have strength in your position. The fact is, it is not difficult for anyone with access to the financial database to change your meal plan - but there may well be an active policy in place and a chain of command, beauracrats, et cetera.
Unfortunately you are either going to accrue body fat if you are stuck on a diet of crap food in the cafe and microwaveable shit, or or you are not going to be able to consume adequate calories, and you're going to lose weight, and muscle.
If, worst case scenario, you are stuck in the dorms - then you better start eating plenty of canned fish, fruit, frozen berries + vegetables, nuts, olive oil, et cetera. Avoid microwaveable dinners like the plague. Avoid high fat+carb meals like sandwiches with shitloads of fatty meats and mayonaisse.
For right now, either use your own car or your friends car to go to Costo and stock up on quality food with your money. Start working on the meal plan situation for next semester. And don't slack, because you will regret it if you're at all serious about your training.