Gefen,
I lived next door to Dovid in my youth. He lived alone and didn’t have much family at the time aside from his mother. She was niftar roughly 15 years ago leaving him alone in this world.
He was somewhat slow and for a time had a job bagging groceries in a Flatbush supermarket.
He would often visit yeshivos such as Torah Temimah, Derech Chaim and others for a warm meal and more importantly, some companionship. He would always have a dvar torah or a joke to try and make people happy.
He would visit Lakewood from time to time, often eating Shabbos meals at the home of the Rosh Yeshiva of BMG, Rav Dovid Schustal who was maspid at the levaya.
This is most of what you will hear about him-was a nice guy who always tried to make people happy.
His petirah is a loss to klal yisroel, especially to the hundreds if not thousands of yeshiva bochurim who knew him fairly well over the years