Having worked in catering (not in a university, but in various naice event venues), I would suggest that cross-contamination may actually be more of an issue there.
I once worked on an event where a guest was allergic to nuts. However, some of the bread rolls had seeds on top, and the chef was concerned that this might trigger the nut allergy 
So, he had us drone-level staff ensure that no one sat near (as in, within about 6 seats radius) had a bread roll within seeds on either. Unfortunately, the bread rolls had come in pre-made, with seedless and seeded all mixed together in a big bag. So, they thought that aerial cross-contamination would be an issue but having been touching each other wouldn't 
When I pointed that out I was told that I wasn't paid to think 
Anyway, the moral of the story is that catering staff often don't understand allergies, and I wouldn't bet that cross-contamination wouldn't be an issue in catered halls.
I'd suggest that her best bet might be to go self catered, ensure that she has taken a full set of her own cooking utensils, and ask people not to use them. If some drunken idiot fellow flatmate was to use one, would washing it be sufficient? If some of this concern stems from an idea of big communal meals, then reassure her that these happen rarely if ever for various reasons (different schedules, different tastes, different budgets, different levels of cooking skill).