The SATCOM is powered by the left Main AC bus. With so many left systems down following an oxygen bottle rupture, conducting the Left Main AC bus checklist will repower SATCOM.
If the L Main AC bus lost power after a bottle rupture, then presumably it was caused by the L GCU and L BTB isolating the damaged bus, or by the L GCU and L BTB themselves being damaged. Either way, how would the ELEC AC BUS L checklist (which requires resets of the L GCU and L BTB) restore power, if the damage was still present?
But, if the aircraft slows to the ECON desc speed as it passes the Top Of Desc point to Banda Aceh, but maintains FL340 (everyone’s deceased), the fuel flow reduces to 6200kg/hr and then down to 5600kg/hr as weight reduces, the aircraft can remain airborne until arc 7, but ONLY IF both bleed air systems have failed since IGARI, and remained failed until 0019:29!
How did you calculate these figures?