Why didn't the other nails have the same material on them if she was clawing at somebody with them?
This is such a nightmare.
But if she was doing her nails, which seems to be the case, the I lost a nail makes no sense. It would be "I was raped and lost a nail and was trying to put new nails on (which were all laid out). The scenario doesn't make sense.
And there's simply too much time passed between whenever she left until she got to the exam.
Give her a lie detector test and get this over with. Damn...