CPS and Assoc.Threatening mediator phone call

Received a call from a mediator for the state of Texas employed by CRS and Associates debt collection company. He called my husband's father and told him that they were filing a levy against my husband for a debt owed on a vehicle and said he needed his address and phone number to send a constable to serve him. I'm not certain what other information about the debt was disclosed to his father. We called the number and the man introduced himself as Paul Sorentino with CRS and Associates. He told my husband that he would have a constable serve him with a levy and everything we own jointly will be taken from us after the judgement. He also said he was going to file a form with the IRS and then the IRS would come after us. He stated that he would decrease the debt by 10,000 if we could pay 4,000 today. He kept telling us if we didn't want to pay then he would consider that a refusal to pay and start the process and we will be served on the 15th. There were many other insulting things that were said, but I will not even get into that. I kept asking when the debt became delinquent and he really didn't know. This vehicle was a voluntary reposession over four years ago. Can they file a lawsuit after 4 years? Can he really have the IRS come after us? Can our community assets be taken and our bank accounts frozen? Lastly, did he break any Texas or federal debt collection laws by discussing the debt information with my husband's father? I have been ill and unable to work and this has hurt our family financially. We are just trying to make it day by day and after that phone call yesterday, I became very ill. It was an awful experience. There is a special place reserved in Hell for those types of individuals... Thank you for any information that you can share to help us resolve this issue.