Hi Chandrakant,
I have also gone through the above website links sometimes back and called the hospital in India as well. They need the visa appointment letter to do the medical test which means the visa appointment is for "consular processing", not for I485. If you happen to go to the USCIS local office, please verify about this. Whether the doctor can do the medical exam for I485 RFE..? Even if the hospital provides the I693 filled form, will it be accepted by USCIS?
Thanks.