There were social network platforms directly for students in Germany for a while.
If one of those is still active in Italy there might be a chance to search via the university.
Figure out the courses inside that room (shouldn't be to many) and use that in the search mentioned above.
Message persons of these courses and ask if they know a person fitting your description.
If such a thing does not exist (anymore) in Italy, checking up on meeting points (library, canteen, general info-boards ect.) of the students would be a more time consuming alternative.
Chances would spike if you can recall a person who talked/standing next to her.