The National Archives does indeed hold the records of the DC local courts, including the now-defunct Supreme Court of the District of Columbia. Regrettably, they don't appear to be available online. This record series looks like it might contain what you're looking for: catalog.archives.gov/id/559838. There's an address there to write to for information about the records: they should be able to make a search and provide copies (for a fee). (NARA is still closed due to COVID, so you might not be able to get a response quickly.) By the way, I presume you've seen the articles in the Evening Star dated May 29 and June 2, 1925? They report about the auto accident and the coroner's report, respectively. Let us know if we may be of further assistance.