Sensible way out would have been for her to offer her resignation, and for the university to refuse the offer, since she'd shown she could do the job.

Some kind of statute of limitations on this kind of thing really ought to apply. Actually legally that would apply to most ex-cons in relation to most jobs. Their problem is liable to be with covering the gap in their career in a way that doesn't reveal what they were doing when they were out of society. (My advice would be, if possible, to use the time to study for a degree - maybe a law degree...)

What worries me, to drift the topic a bit, is the way that increasingly it's becoming impossible for young people even to get considered for all kinds of jobs if they haven't got formal qualifications which are completely irrelevant to the job. So they either get the qualifications, and in the process run up enormous debts, or maybe they fib, and start their lives on a precarious basis of dishonesty.