[help] Bought A Car Off Facebook Marketplace And Now The Original Owner Says She Wants Nothing To Do With The Car And Will Call Law Enforcement If We Attempt To Contact Her Regarding The Matter Again

Location: North Carolina, Wilkesboro (seller) and Waxhaw (me)

Background: So about a week ago me and my dad bought a car for 3,000 dollars off of Facebook marketplace. The guy we bought it from runs a body shop and was driving the car around with a dealers license so when we brought it home we had to drive it with no plate, no big deal we just get a new one when we get home and have the title notarized as a buyer, which is where our problem started.

Main Issue: When we went to get the title notarized we realized that the original seller (F 85-87) did not have her signature on the title notarized to sell it, and since the guy we bought it from was using a dealer plate he hadn't signed the title as a buyer. We found the lady's address and phone number from voter records and attempted to contact her asking if she could get her portion of the title notarized so that we would be able to register the car. After calling and leaving a message we waited a few days and still got no response. After that we went to Facebook and managed to find her daughters and one of her neighbors to see if they had any information on how to contact her. Neither of her daughters responded, but her neighbor did, and fortunately she used to be a notary so she was able to understand our predicament and help us out. She reached out to the original owner on our behalf and told us that she said "I blocked their phone number, I sold that car to the dealer (Facebook marketplace guy), I have nothing to do with that car and I don't want to see them again, if they try to contact me again or show up to my house I will call the cops on them." me and my dad were taken aback by this response and now have no idea how we should proceed, the neighbor who used to be a notary told us that if we knew a notary we might be able to get them to notarize it without her presence, but we do not know a notary and that is illegal so we would not want to resort to that. Any advice on how we should continue would be greatly appreciated.

TL;DR bought a car off Facebook, seller didn't sign the title and the original owner did, but her signature is not notarized

Edit: My dad and I are going to file a police report against the seller and contact him to ask for our money back, If he doesn't send it back we'll go about disputing the check with the bank (Wells Fargo)