If your parents are not in the position to ignore these calls- then this IS on you.
Can you change their number? Have your lawyer write a polite but strongly worded letter to the party contacting your parents saying "cut it out- or we're going to the police for harassment".
What do your parents know of the situation? what have you talked to them about?
I feel your pain- I brought the entirety of my shitty and dangerous situation with my ex to my parents home. They've had to deal with safety plans, criminal proceedings, etc etc...I talk to them about it though and you know, apologize profusely- and let them vent. A lot of time- people who are on the perimeter of a high conflict divorce- they get hit by the shrapnel. They're pissed about being put in the situation- and they need an outlet to vent. It's a lot that we ask of these people.