As I wrote in my last post, I sent a letter to the Presidency of the Seventies about Dave's bizarre behavior. I recently heard back from them.
They thanked me for sharing my experience with Dave and for my efforts in expressing my feelings. They then wrote: "Please know that we will ensure that the proper steps are taken to counsel (Dave)."
That was all I needed, to know that someone heard me and would do something about the situation. Thank you, Elder CCC of the Presidency of the Seventies.