Garage Redevelopement in Co-op Hsg Soc

Sir, I stay in co-op hsg soc building in pune city (within municipal limits) which has 12 flats and 1 (detached/covered/ closed) garage of 200 sq ft nearby in its premises. All the 12 flat owners are members of society. Garage is owned by one of the flat owners. That flat owner's father owned vacant land on which the building and garage stand today. Original Developer gave his father two flats and one garage. Later, after death of his father, he sold one flat to other person. Now that flat owner is part of society as ‘flat owner’ and not part of society as 'garage owner'. Society does not spend on garage maintenance. The garage is kept locked and not used for parking / residential/ commercial purpose etc. The garage doesn't have separate light meter. There is temporary wiring from flat owner's meter to his garage. There MAY not be any separate corporation property tax account for garage. We have registered sale deed done by original developer with this flat owner cum garage owner's father's consent for complete plot on which flat and building stands today. This sale deed is in favour of our society.Now we are thinking of redevelopment of society building. Selected developer has asked the flat owner cum garage owner to accept financial compensation in lieu garage. But that flat owner doesn't want financial compensation. The developer is ready to give him a complete 800 sq ft area 2 BHK flat with open parking in one of developer's other schemes outside pune city (outside municipal limits) in lieu of garage. Developer is asking garage owner to pay amount of 2 lakhs and stamp duty + registration fees (almost 1.5 lakhs).That flat will be ready in six months. Our redeveloped building will be ready in 2 years from date of signing of agreement with developer. Garage owner is willing to accept the flat there but says that developer should not demand any amount and stamp duty + registration fees should be paid by developer. He says that there is difference of market rates of both locations. Developer is not willing to accept his logic and says the flat price outside pune city already exceeds garage value. Alternatively, garage owner is demanding additional area equivalent of garage area in his redeveloped flat, in addition to free area offered by developer to him as a flat owner. Otherwise he is demanding a separate unit in lieu of garage in redeveloped building apart from his redeveloped flat. He wants this unit to be of existing garage area + proportionate free area offer given to flat owners. Developer is not ready for this option. Developer cannot build new building keeping the garage ‘as is where is’. Is it legal to accommodate separate unit in lieu of garage in redeveloped building when 'garage owner' is not part of society.So even if all 12 members are ready for redevelopment , the agreement cannot be signed because of 'garage owner', a non member of society. Kindly advice what action should be taken by society. Regards, V. D. , Pune