If you did, then bring the copy of them to your exit interview with HR. Complain to HR about his bully behavior. Tell them you reserve the right for further legal action pending their decision on your PTO payout.
I normally don't like any bridge burning action, but this is not acceptable. Fight for your rights.
I do suggest you complete the transition and document it. You need to finish your job regardless how they treat you. That will be good the evidence and supporting document for the future reference if needed.