What can my mom do to get her deceased brother's house?

The attorneys are only interested in money and they keep trying to get her to buy a different house. He's been dead for a few years and there's no known will. He still has payments left on the house and the mortgage company is still trying to get a hold of him for the money. Most people say to go to probate but it just goes back to the attorneys wanting money. My mom and her brother are blood related and there are no other relatives she knows of. My mom refuses to talk to the mortgage company because he assumes they'd say they don't want to talk to her they want to talk to her brother and she won't tell them he's dead in fear she'll lose her chance to get the house. Any suggestions on what she can do?