Appeal against the inquiry report submitted to the DPCA

The complaint was registered at District Police Complaints Authority (DPCA) in Karnataka against the misconduct of a police officer who is DSP now and then CPI at the time of inquiry-1. The inquiry officer (ASP) appointed by DPCA had considered/taken false and fake statements from the witnesses and possibly without their knowledge about what exactly they have given statements but sign belongs to the witnesses and they are not aware of content in the statements. The inquiry officer did not consider my voice recording of the inquiry-1, in which police officer had threatened my family and used abusive language to us. Because of this issue, my family is facing humiliation in the society and problem is still persistent even it is almost two years after approaching the police for the help. Interestingly one of the witnesses had given two statements with same content but there is difference at the signature of the inquiry officer and thump impression of the witness. I have copies of these statements with attestation by the SPIO. I have contacted one of the witnesses, who was not present at the time of inquiry-1 but taken statement from him forcibly without the presence of the ASP and he is not aware of the content in the statement too. However, he is ready to explain what happened before concerned authority if it desires to reconsider his statement. Hence, inquiry report is in favour of the accused DSP and submitted to the DPCA. It is worth to mention here that I am not able to access the information under RTI act and it always denied by the SPIO and DPCA staff is not responding to my queries and not intimating DPCA meetings details properly. I not yet attended single DPCA meeting for the complaint registered in May 2017. These issues are already intimated to the DPCA via letter. Initially we approached to Police to stop the forcible marriage of my differently-abled brother and my family belongs to the ST community. Hence, hereby I am seeking your helpful advices in this regard: (1) Can I appeal against the inquiry report? if yes whom to approach for the appeal? (2) Whom the fake witness has to request to reconsider his statement? Is there any other authority to take statement from him other than Police? There is a possibility that police cannot take statement from him now. (3) How can I make my voice recording as my strongest evidance? So that false and fake witnesses can be suppressed. Thank you for your advice.