The message was from a man telling me (with extreme profanity) to leave her alone.
Whatever the reason she's contacting you for is not good. Right? It's either some weird drama, crazy stalking or she's setting you up for this dude to yell at you.
NC all the way seems to be your escape. Don't get in trouble with this guy either. If she's telling people lies that your harassing her nothing really you can do right? Probably best to stay above all of that.
My advice is enjoy life now without the extra headache that she is attempting to give you.
Peace,
AO