Is she still getting phone calls?
If so is she 100% sure it's him?
If the answer's to the above is yes,take note of the time and date and what was said.
Then go to the police and say you want him charged with assault.
If he made threats to hurt her say to the police what he said and that she honestlly belives he will and can,and she fears for her life.
I think your right about the note if it was a MC the job would have been done by now.
If that fails a bat will work well,start with the knees LOL.