Collect all the evidences after filing application under the RTI Act 2005.Do not waste the time. Division of Muslims property is a very hectic and tough matter and a very very complicated law as the distribution is made in accordance with the dictates in Quran. All can not do that until they are very expert on Quranic issues. It will be better if you also contact Imarate-Shariya Phuwarisharief Bihar and send them the details of properties and the list of the claimant relatives.You can visit their web site also to get the information.But please do not approach Tipu Sultan Mosque in Kolkata. Their calculations and divisions are based on consideration for money as to what you give to them. Infact I am sorry to say that they are ignorant of Quranic laws on the issues concerning the division of properties and the ration as per Quran.Imarat Shariya can be depended and so the Darul Uloom Deoband or Nadwatul Uloom Lucknow.They will issue a distribution of property list as per ratio of the relatives which you can get translated in Bengali or English from the approved translator and can use it as a piece of evidence in the court cases.It is up to the Ld.court whether it accepts it or not or uses its own wisdon but that will be a piece of evidence which can not be ignored also.