Are you looking for an autopsy report?
Yes please and any investigator notes.
Examination reports, more commonly known as autopsies are open to the public, additionally, the state of Delaware does not charge a fee for these reports. To get the examination report, you need to request them directly from the Delaware Division of Forensic Science, 200 S. Adams Street Wilmington, DE 19801. You will need to provide them your name and where you choose to have the report sent (a mailing address), the name and date of death of the deceased. You can also find their contact phone numbers listed on Division of Forensic Science's website. Delaware Code: Title 29, Section 4706 states the types of deaths that are investigated. DDFS has an administrative office six staff members (director, deputy director, chief medical examiner and 3 deputy chief medical examiners) maintaining pathology, death investigation, toxicology and controlled substance records/reports. Their email address and names are listed on the DDFS website if you need to contact them directly.
There are free searches which show property information online freely, you will need to know the county, since there are only three counties in Delaware, you can just look into them individually. Sussex, Kent and New Castle, all three have free online searches of property information. You can search by street name or other location description.
There are many sites where you can look up arrests, including: Delaware Criminal Justice Information System Online Wanted Person Review, this is a free and instant search from the state. What the state police provides should be on their webpage, or you may need to call. I would rely on information directly from the source, not another person's experience as it can vary from one individual to another. Note that arrests do not always end up as criminal convictions, chances are that they wouldn't appear in a person's background check.
The Chancery Court appoints guardianships, which include guardianship of an adult, property of an adult and property of a child under the age of 18. The Delaware state courts' site offers an overview of the process for a disabled person's guardianship.
Since you know the date of the incident, periodicals such as the one at the local library could have an article about it. Crime mapping, there are several different sources, also show fires (possible arsons) by area/block, this source has dates of coverage and various departments. If you know the location or city of the fire, mention it in your question, there may be a source specific to that area. Some fire departments release press releases and news about their operations.
You do not necessarily need to know which county to conduct the search. You can request a criminal search from the central repository for criminal history information in the state of Delaware using the State Bureau of Identification. You can also look up addresses found by doing a people search online. Some addresses or residences can be cross referenced by looking up deed information and property ownership. Also, keep in mind that juvenile records are not available through this service. Similar to criminal records, the state's superior court's case search can be looked up at once where you may not need to go from county to county. You can access cases and judgments under persons' names as well as businesses.