Problem solved!
Just called Jakarta (can't wait for 2 days for SF office and Jakarta office to communicate with 14 hours time difference

) and they confirmed that the ticket can be rerouted for $20 penalty fee (yayyyy).
So I will be flying on the 18th if everything runs smoothly. Still have to find a seat on UA for 18th morning tho...
Anyway, thank you so much EVA air for your advises. Trully appreciate it. ^