Can an attorney us a DV letter that was sent to another CA

I recently received a letter from Michael J. Scott, PC Attorneys and Counselors at Law in Carrolton, TX. The letter was dated July 22, 2010. It stated that it was written response to my request that they verify a debt from Citibank. I did not recall any communication from this office or written notice that they were trying to collect a debt. I don't normally call, but I did call this firm. I began questioning the letter and why it was sent to me since I had not requested anything from them and had no prior communication with or from them. The employee apparently began running through information on her computer screen and revealed that a letter had been sent to me on May 4th and I had sent a written request for DV that was received on May 24th. I looked at my file and these letters that she was referring to were from a CA in Toledo OH with a completely different name and no reference to this firm in Texas. I did receive a letter from this CA and I also sent them a DV request by certified mail that was received on May 24th. So...can this attorney in Carrolton, TX, who I had no knowledge of, use correspondence that I had with a CA in Toledo, Oh, as if it were communication between his office and myself??? I also gathered from the employee of this firm in Texas that the letters they had in their computer files were letters that had perhaps been scanned in and received from Citibank. I ended up speaking to an attorney in this firm, who really wouldn't give me any information and told me she was going to end our conversation if I didn't have any questions. I did have questions, but she wouldn't answer them. She also led me to believe that I would be sued soon.
I immediately called the CA in Oh and was told that they cancelled the debt on May26th after receiving my DV request on May 24th and that they no longer had any business with me. I callled Citibank and was told that Michael J. Scott was a legal advisor working on behalf of Citibank to resolve the said debt, but that he was not going to take legal action against me nor sue me. I tried to gather more information, but eventually she told me I would have to contact the attorney's office for more information.
I feel like this Texas attorney has done several things to violate the FDCPA, but at the same time I'm really afraid of being sued. I did some research and found that he has sued some Texas residents on behalf of Citibank--it was public information in a newspaper article. I also found some information on another lawyer's web site that shows Mr. Scott's plaintiffs have dismissed cases before trial but...I'm beginning to think these lawyers are working together and both are benefiting from these cases. I don't trust anyone.
I guess my bottom line question is can this Texas Attorney use the correspondece between myself and another CA as if it were correspondence between his firm and myself? My gut tells me he can't, but he's an attorney, so I'm a little afraid to challenge this and send him a certified letter disputing all of this and citing what I think his office has done to violate the FDCPA. Any advice?