You have to be careful with the writer. Have you listen to his or her demands and why did you arrive at this situation. Some writers are suicidal at worst. Forwarding your emails to your university would complicate the issue since it will be a proof of complacency and participation. The paypal receipt is also further proof. Your best bet is to sort out the issue amicably with your writer since you can pretty much get messed up by Turnitin if the work is published online. You will be in great trouble trying to explicate yourself in case of plagiarism. All the best though
