What documents to be asked

We are a CHS society.Our developer xyz has sold one flat free of cost thru it's partner A ( promoter/ developer) to B (Allottee/Land owner) free of cost with C as " confirming party ". The transfer deed is done and registered but society was not told about it as maintenance bill is still raised in the name of developer xyz. A&B are brothers and C is the father and said property is the ancestral property of C who is also ---" Confirming party " in the transfer deed . B has passed away and is no more.Further wife of B has requested the flat to be transferred in her and two childrens name. Now our query is as follows: (1) is B the sole owner or now C or his remaining sons can claim the property also (2) whose name share certificate has to be prepared(3)what documents we have to ask from wife and children (4) what care should society take for indemnifying itself and it's members from future issues / litigation (5)what is the meaning of " confirming party " in legal terms. Please guide us and requesting to reply or answer question wise...1..2..3..4..5..