Resubmitting the FOIA request won't get you any better results than before. Under Delaware's FOIA law (and it is the state FOIA law that applies, not the federal FOIA) there are a number of records that are exempt from disclosure. As it applies to criminal matters, the law excludes most every record in a criminal matter from FOIA. Specifically, the law states that the following criminal records are excluded:
(3) Investigatory files compiled for civil or criminal law-enforcement purposes including pending investigative files, pretrial and presentence investigations and child custody and adoption files where there is no criminal complaint at issue;
(4) Criminal files and criminal records, the disclosure of which would constitute an invasion of personal privacy. Any person may, upon proof of identity, obtain a copy of the person’s personal criminal record. All other criminal records and files are closed to public scrutiny. Agencies holding such criminal records may delete any information, before release, which would disclose the names of witnesses, intelligence personnel and aids or any other information of a privileged and confidential nature;
(5) Intelligence files compiled for law-enforcement purposes, the disclosure of which could constitute an endangerment to the local, state or national welfare and security;
DE Code title 29 § 10002(l). As you can see, you can get your own criminal record (the record of your arrests and convictions) but the police may deny you all the investigation materials, witness reports, etc., that are connected with this incident.
If you believe that your rights were violated and wish to sue the police then see an attorney who litigates civil rights matters. Even if the state law wouldn't permit a lawsuit at this point for failure to submit a timely administrative claim (and I've not checked Delaware law on that) adjusterjack is quite wrong to suggest that would prevent you from successfully suing. You may still have at least a federal civil rights lawsuit to pursue, and you do not have to comply with state law regarding administrative claims prior to filing a federal lawsuit against the police.