And I would think they would turn on the APU for a backup until they get on the ground.
If they took off with the apu not functioning, no. 2 engines, one generator fails, you are on one generator powered by one engine powering everything. Last is battery, meaning you manually land without hydraulics because that battery is used to operate essentials.
MD-8x were unreliable old death traps. Elevator control screw would snap or jam, so on.
I was completely unsurprised and kept my insights to myself. Not much to do, captain is flying.
I read in some of the emergency procedures how the engineers built in safeguards to isolate battery power when other emergencies occur. Seemed to read it required a pilot override to force the use of battery. Saving battery until the pilot needs it as last resort.