I listed every single creditor from all three reports- I knew that some were the OC's and some were the CA's for the OC's, but I didn't care. I was much more afraid of missing something that of duplicating something.
I also went through every piece of paper in my office, and every single bill that I could find I included those as well, especially if they were not at a collection agency. I left no stone unturned in this process because I didn't want anything to come back to haunt us after the fact, and nothing has.
I showed up with a mountain of papers to my attorney's office the day we did that part of the paperwork.