Here's a thought.
I would make it totally a legal letter. By you mentioning disassociation, you are in effect, giving them permission to disfellowship you.
I would take out the following material
There is nothing I see in the Bible that calls for a formal letter of disassociation in my situation, or any other. I did not sign a contract with an organization at my baptism . In 1978 baptism was still a dedication to God not an organization like it is today . It seems to me that the provision of formal disassociation is a matter of convenience for the Elder body or the Society rather than serving any real religious purpose. It allows people to be pigeon-holed into nice neat little categories rather than dealing with real issues .
My spirituality is between me and my heavenly Father . I wish to be left alone and allowed to seek that journey on my own .
Since you are involving the police, just leave it legal, and let them sulk in their own sour milk.
Great letter btw.