You're mixing FIR with charge sheet alias final police report, former is an initial report which contains compliant registered by the complainant and latter is a document made post investigation which contains findings, witnesses account, affidavits and stuff.
Complainant is all entitled to get complaint registered in his/her way, unless FIR is sealed press/media/concerned parties have access to information registered in FIR.
This would help you understand what information needs to be provided in charge sheet or final report.
SALIENT FEATURES TO BE REMEMBERED WHILE PREPARING FINAL FORM / REPORT (I.F. 5) (i). The name of the court shall be indicated. (ii). The final report / charge sheet number should be given serially. (iii). Sections and Acts shall be clearly mentioned. (iv). The type of final report such as charge-sheet, untraced, mistake of fact, etc shall be clearly indicated. (v). Name(s) of the investigating officer shall be furnished (vi). Details of things / properties seized shall be properly accounted and sent in the prescribed list. (vii). Particulars of accused persons shall be furnished a separate sheet must be used for each accused. (viii). Status of the accused such as bail, absconding, forwarded, etc., shall be mentioned. (ix). Particulars of the accused persons not charged shall also be furnished. (x). The number of RCS notice / complainant notice shall be mentioned. (xi). List of witnesses to be examined shall be furnished. (xii). If the case is a false one, indication about the proposal to take action under section 182 / 211 IPC should be made. (xiii). Result of the CFSL report (Central Forensic Science Laboratory) shall be furnished. (xiv).
Facts of the charge with brief accounts of the motive, preparation, subsequent / previous conduct, the modus operandi adopted in the property offences shall be presented in clear and legal terms. (xv). The final report / charge sheet shall be sent to the court which shall include
http://police.pondicherry.gov.in/Police manual/Chapter PDF/CHAPTER 38 H Completion of Investigation and Final Report.pdf