Yes, you can file RTI Mumbai Metropolitan Region Development Authority (MMRDA).
MMRDA is a body of the Government of Maharashtra responsible for the infrastructure development of the Mumbai Metropolitan Region. It was established in accordance with the Mumbai Metropolitan Development Act, 1974, on 26th January, 1975. Hence, MMRDA is a "Public Authority" as per Section 2 (h) of the RTI Act and falls under its ambit.
You can file RTI Application to MMRDA by addressing the same to the designated "Public Information Officer (PIO)" and by paying the prescribed fee.
To know more about the procedure to file RTI Applications in the State of Maharshtra, please refer https://onlinerti.com/how-to-file-rti-online-for-maharashtra