Generally in cases relating to the ADA and reasonable accommodation, the employer has the right to request and review medical records supporting the disability. The doctor must also state if the employee can be accommodated and if so, what the doctor the doctor recommends (if any) which would allow you to return to work.

However, this information should not become "company gossip." It is in appropriate to share with anyone other than those who would review the file or determine if, for that company, the accommodation is reasonable.

It seems you are already, correctly, with the EEOC (thus cannot take private action for at least 180 or when the EEOC makes a ruling).

Remember the EEOC is not your attorney, their job is to investigate what amounts to a criminal (in the sense the ADA is a law). They may ask you and your employer to mediate, but that is in special circumstances.

If you feel that you are being asked in appropriate questions, I would call your EEOC Investigator and get recommendations from him/her or better yet have a letter sent from the EEOC to the Employer explaining what they are and are not allowed to do.

While you cannot sue at this point, you can hire an attorney to represent you in the EEOC action. The employer will likely involve a law firm to respond to the complaint. It will be your responsibility to file a rebuttal. Attorneys can (in many cases) be helpful in determining the scope of the answers, the supporting evidence, and other issues which may strengthen your case.

I know this is a lot, but I hope it helps!