Probate Vs. Release Deed

Facts: 1) I am the sole nominee on a property jointly owned by my parents in Mumbai. 2) My parents had Wills where I am to inherit their respective shares for the said immovable property. 3) My parents passed away a couple of years ago. The co-op society transferred my father's share to me based on the nomination on record in 2017. 4) Society is now stating that due to a change in law in 2019, I can be admitted as a provisional member only. I would need to submit either a Probate of Will or Release Deed from my siblings. Questions: 1) Instead of going through a Probate route (longer and time consuming), can we enter into a Release Deed where my siblings relinquish their "rights"? 2) I understand that Release Deeds is done when there is no Will. However, is there any limitation in law that would bar us from executing a Release Deed in our case? 3) Can the Release Deed be structured WITHOUT stating that parents passed away intestate?