FIR against my sister & husband registered under sections 323 324

Sir, my sister was molested in her house by a tailor. she called her husband from her work and instead of going to the police they together went to the shop of the tailor where he worked and slapped him and beat him with belt. The tailor in front of all other staff apologised and pleaded forgiveness which was done so and his employer was also informed about the same, and mentioned to her that we do not wish to file a police complaint as he has apologized for his immoral act and behaviour. All this was recorded in the CCTV camera in the shop. Thereafter my sister and her husband both left on the same day to Delhi for about 7 days or so. In the meanwhile the owner and the tailor both went and registered an FIR against my sister and unknown person (her husband) as in the FIR and a criminal case was registered u/s 323 and 324. medical certificates and recording was submitted to the police which is on record. Thereafter, on my sister and her husband's return from Delhi we came to know that behind this an FIR has been registered and the Police wanted to arrest them for the said offences. We on the very same day got registered an FIR with the same Police station stating what had transpired on that day and our FIR (very reluctantly) was somehow registered with great difficutly u/s 354,341 and 506. However, thereafter the tailor has not been arrested until date and none of us have been arrested. We had met the DCP of the concerned Zone and submitted an application from our side stating that in the FIR the Tailor himself has admitted in the body of the statement about his immoral behaviour and also in the summary of the statement recorded by the Police completing the FIR, and the reason of him getting beating from my sister and her husband. We also explained to the DCP about why a belt is not a weapon and moreover the tailor's own admission shows enough that the FIR was registered on some behest and in a haste without finding and waiting for the other sides facts. The DCP took congnizance of the application and forwarded to the local Police Station as our application stated that a Closure should be done and section 324 is not applicable and 323 is non-cognizable and an "NC Final" Closure report should be made and FIR should be considered false and frivolous one on the basis of the application and after conducting primilinary investigation and taking down the final statement. Thereafter, in the meanwhile the local police guys to help the other side seeing our application, requested the Tailor's owner to ask us to consider for an amicable settlement and make an application before them for withdrawl of complaint stating that we have reached amicable settlement and none of the complainants want to persue with the matter and hence an closure report in both the cases be done and filed be closed at the police level and out of court. We submitted to the Police the letter of consent reached between both of us, and thereafter also reported the same to the DCP who inturn said the ACP has the powers to drop the FIR after taking final statement of both the sides. Please guide us Whether the Police can file an Closure Report under such an Settlement Reached between both the parties without either of them going to the Court or that it will be essential or law to appear before the court for giving final statement and only then can a closure can happen. Also let me know if the Police if have powers to file for an closure report and no arrests have been made and no chargesheet filed, no investigation done......can be completed and closed at their level and under which type of closure report.......please guide how much time it will take to complete filing the closure report as the first FIR was 24/10/2016 (section 323,324) and second one by us was on 02/11/2016 (section 354,341,506)