Mine is a federal debt and is worse than bankruptcy?

I have an outstanding credit card with the army exchange. I am retired coast guard and have had some rough times since I have retired in 05. We did owe about $5,000 on this card but trying to stay above water with my mortgage we let the credit card get behind. A company called NCO called my work looking for me so I tried to call them back over a 5 day period with no luck getting through. I got hold of a person named Todd Lane who had called my work looking for me. He is from NCO. I talked to him on 1/19/09. He informed me that this is a federal debt and is worse than bankruptcy. He told me that I owed $6900 and that the federal government was going to garnish my retirement and any tax returns. He then told me that if I paid him $2075.00 now and $400.00 a month he would not send a fax to my job and start a min 15% wage garnishment at my regular job. I told him that I did not have that much money to put down but could pay him 400-$500 a month. He said I needed to go to a bank and get a loan to pay him. He tried pushing the Navy Federal Credit Union on me. I told him that I could not pull a loan with my credit the way it was and we are trying to heal my credit. He wanted me to get a co-signer for a loan. I told him that I needed to talk to my wife about this. He said I had 24 hours before he sends a fax to my work and garnish my wages. I don’t know where to go with this. I want to work with them but I can’t get my job involved. Please help me.