SRA builder Dhanista group not built any flats,false promise delayed for more than 8 yrs

We group of 30 people came together and filed a case against Dhanishta developers who promised us to give flats at economical rate within 2015 he promised we will get our possession. We had rendered our amount in 2008-09 half in cheque and half amount in cash ,builder requested almost 40 percentage of total agreement value to be paid even without an OC recd... After 2015 since builders failed to build a flat we requested for withdrawing back our amount, there he started Making excuses of builders funds r stuck, we also agreed on builder if he can release part payments so it will not be a burden. Everytime he used to call us in office make us wait as we are there for some favour or to beg and tell us excuses they don't have money.because of them my mummy had hypertension issues and high diabetes because every time they used to cLl her also on mail they promised money to be refunded. We also had some cheques bounced once of 2 lacs rupees.. Then we filed a FIR with Vikroli parksite police by first 10 members of our group out of 30-31 as trial which was very difficult initially then somehow FIR was accepted and later we went to hire a lawyer after which the Builders bail was rejected and he was behind the bars... We don't want Him or his children to go in jail but we want a solution for our money back... Please suggest some ways as the lawyer has finished his work by putting him behind the bars but we want some one who can fight till end and get our money back. What is Writ application. What is arbitration clause... Need to know answers on this... Please help