Cancellation/Declaration of sale deed as void

Part-2 Hello.. I'm Shiva Prasad Udari from Hyderabad, Telangana. 8. We left with no choice. Soon after we came to know that the buyer after 8 yrs(2013) by maintaining MRO officials illegally he succeeded in abtaining proceeding for mutation in 2015, he managed to get it in the name of Jangaiah s/o Narsaiah who died in 1997. 9. After approaching MRO we left with only one choice to fight against him i.e, in Civil Court. We A & D approached a lawyer and 10. Son of A who is my brother(had 18+ age in 2005 & not signed in sale deeds) have filed a suit in Mdl.Court with O.S XX in 2015 before Pr. Jr. Civil Judge, claiming- Suit for partition & Separate possession under Sec-26 Order-VII Rule-1 of C.P.C. Few months back the case is at trials stage. 11. Also we have filed an Appeal before RDO against the proceeding files under Sec 5(5) of the ROR in Lands Act. in 2015. 12. D has expired in Dec-2016 and now his wife, brother-in-laws and wife of B are threatning us & my brother/Plaintiff to sign before MRO and in Lokh Adalat (these people also forcing us by contacting through phone) to sign. So that B & D on their own can apply and get PB & TD. But the actual thing is the buyer is guiding them to do something to get sign of plaintiff. Can't we expect something worst in this scenario..??? I'm the son of C & My queries about this are: (a) What are the chances in my case. (b) What are the key points too cancel sale deeds. (c) While researching in internet I've read that, a sale deed must and should have atleast two witnesses are mandate other than beneficiaries of land- Is that true..??? (d) Also read that such documents which are not executed according to rules can be declared as void/null by any authority like RDO- Is that true..?? (e) With pending suit in civil court, does RDO authority can cancel proceedings after proving the same as above.?? How much time does it take.?? Next hearing date in RDO is 20- Mar-2018. (f) If proceedings have cancelled, can we apply for shares for separate Possession and Patta(Locally known as "Virasat")..?? ::Pleading:: Please provide the links/reference of Acts, Rules, Sections, etc, for above queries. ::Thanks alot in Advance::