RJMDVD is most likely RJM ACQUISITIONS LLC which is a Collection Agency.
RJM Acquisitions
LLC 575 Underhill Blvd. Suite 224
Syosset, NY 11791-3416
Phone Number: (516) 714-1300 (800) 541-0824
If the disputes from the Credit Bureaus come back as verified and remain you will have to take the next step. That is per the Fair Debt Collection Practices Act(FDCPA) you are allowed to request Debt Validation from them. There are several examples of a DV letter on the Internet. But just a couple of other pieces of advise send it by Certified Mail with Return Receipt, and do not sign the letter(only type your name).
If they do not validate the debt, they are required to remove the listing from your credit report and stop all further collection activities. If they do validate the debt, you will have to deal with that as to what the next step would be.