Thanks Perp. I wrote a much longer answer but lost it before posting.
What I added to your comment, is that I have also told her that if it suits her (and only IF) when he pops around again and tries to scare her out again, she could negotiate with him.
I know a couple who were offered, and accepted, $10K to move out earlier than their lease end.
And earlier this year, we gave our tenant the final four weeks rent-free if he agreed to break his lease so we could offer the house for sale with vacant possession.
It meant we were not "losing" more than half the market and we got it in writing.
She knows to get anything in writing and I think she will certainly check with someone before going down this path.