itsnotthatbloodyhard
The turn back radius indicates a turn radius of approximately 25 degrees angle of bank.
Given the speed, this is beyond the capabilities of LNAV. The turn back is either conducted manually or with the autopilot in heading mode.
The lateral tracking towards Penang, as observed by primary radar, is not via waypoints and has multiple minor heading changes. It is not tracking in LNAV, it is still being flown manually or by the autopilot in heading mode with minor heading changes.
The flightpath from south of Penang through the Malacca Strait is via waypoints. It is most likely now tracking in LNAV.