I currently have a charge file with DCOHR for age discrimination - Company first filed a motion to dismiss- asserting I did not work for the company , after researching I was able to provide DCOHR with W-2 with company name that I filed against and DCOHR continued may case. I notices that company has me as an employee under another one of their collective groups of companies, I want to sue them in District Court as well. Do I have a legal right to do this?
Your question isn't the clearest, but I think you may have the right idea. If you have a W-2 from one company, which it claims it does not employ you, and another company lists you as their employee, I would certainly consider starting by suing both. You should find counsel who can assist you in sorting this out, and of course, in accomplishing the far more difficult task of succeeding in your discrimination case overall
This is not formal legal advice.