Sabah Wildlife Department director Augustine Tuuga said they have no new leads or suspects in this case.
The source of bullets used in the killing was also untraceable, he added.
“We were banking on having these bullets traced to find out where they came from,” said Tuuga.
The 10-year-old pygmy elephant was found killed at a plantation close to the Malua Forest Reserve in Sabah’s east coast Kinabatangan on Aug 4.
The jumbo was first discovered still alive by plantation workers at 7am but when wildlife officers arrived on Aug 6, it was already dead.
Late 2016, three pygmy elephants, including a rare sabre tusk jumbo, were killed in the Segama area. The poachers were never found.
Apart from poaching threats, human-elephant conflicts on the east coast have seen landowners killing the animals when trying to stop them from destroying their crops.