SkyTeam member airline Xiamen has LAX to Jakarta, Indonesia for $437 round trip March to early May. From Jakarta there are several airlines offering round trip flights to Bali DPS for $73 to $83 round trip.
These low fare tickets book in Xiamen Economy S, which does not earn miles in any SkyTeam frequent flyer programs.
There are one stop and two stop itineraries for LAX-CGK. The two stop itineraries tend to have shorter layover times, while one stop allows time for a day time hotel in Xiamen.
Xiamen Airlines LAX – Xiamen XMN – Jakarta CGK – Xiamen XMN – Qingdao TAO – LAX
These fares are available through Xiamen website and other OTA sites. Expedia offers $1 discount.
Jakarta – Bali Denpasar DPS
There are lower fares between Jakarta and Bali. I picked this itinerary solely to fit within the Xiamen ticket times. There are many dates with low Xiamen fares for LAX to Indonesia and most flights between Jakarta and Bali average $40 each way.