If you want the judge to hear facts based on your personal knowledge you need to file a declaration (See California Judicial Counsel Form CM-030) and serve it on the other side. If you want the judge to look at a document you need to bring the document to court and try to move it into evidence. The document would almost certainly be hearsay, so, I would read California Code of Evidence 1200. (If the report is going to come into evidence it will probably come in under 1270 through 1280)
I am unable to find any information for you regarding which Judge is assigned to Department 3. Department 3, the Family Law Department, is located in the Nevada City Historical Courthouse and Annex which is located at 201 Church St, Nevada City, CA 95959. I would mail your response to that address, to the attention of the Family Law Clerk, Attention: Department 3.
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