The Bungalow, Quarry Bay [????-????]
The Bungalow is indeed the building you identified on the map, with the "Bungalow Dam" above it. This was Dockyard staff accommodation too, with 2 - 3 single storey apartments all on one level. I don't know when or why it was built, but it was probably initially for senior executives similar to the 2 Kornhill buildings.
It was a long way up from Kings Rd, with no vehicular access [ditto Stanley Tce], but there were 2 or 3 sedan chairs waiting at the road, and the coolies were provided with accommodation on the spot by the Dockyard.