Seeking sole ownership of jointly owned flat from estranged wife

Sir/madam - I had posted below question: https://www.kaanoon.com/300513/estranged-wife-asked-bank-to-auction-jointly-owned-flat also transferred to wife's a/c an amount = 6 months of EMIs so that she can pay till we resolve the issue. However she still refused to pay EMIs or withdraw auction request or return transferred money by falsely claiming it was owed to her as agreed previously. After your advice, I sorted the issue with bank to pay EMIs on my own & offered to buy my wife's investment/share at prevailing market rate. She is now exaggerating her share by claiming to have paid: 1) fictitious payments to builder (no proof) 2) home loan processing fee of 70K (loan statement shows 9K). 3) my seed money prior to purchase (transferred via EFT) as her investment. She mentioned above in email titled "Acceptance of her investments" & asking me to accept. I did not accept the amounts but agreed to pay in order to enable mutual divorce. We agreed to sign an agreement to pay in 6 months as I need to raise capital by auctioning a property. In meantime file mutual divorce petition. She was informed registrations in our residing state Telangana were stayed by High Court since 3 months so even if I pay her we can't re-register the flat. However, she now wants: • To be paid within 45 days in 3 instalments of 15 days with post-dated cheques. • Additional Interest @10% p/a on total claimed amount. • A set of keys to the empty flat till I have fulfilled above conditions. Else would proceed with 498a. Faced with extortion I clarified to her that am not willing to pay any more than her actual investment & that she has a set of keys already but have received no response. Am currently pursuing masters (on break from job) and EMIs are quickly dwindling my savings. Kindly suggest legal remedy for my situation: • Can I file civil case for transfer of complete property title by agreeing to pay her investment/share established by court and how. • In meantime can I occupy the vacant flat or give it on rent. Any other measure you deem appropriate.