Hello Disneygram, to me the white spots seems to be some type of mildew. See these links that talks about mildew, powdery mildew and downy mildew
http://homeguides.sfgate.com/w...
https://www.planetnatural.com/...
It has some suggestions there how to try and treat it, the only thing is, your plant is in so much stress already. There has been too much root disturbance as well, I did not disturb the root zone of my plant then as I waited patiently for it to recover.
It will be up to you, if you want to continue trying to revive the plant, just be careful you do not infect other plants that you may have indoors as well. Make sure to quarantine it from other plants. Or just ditch it, and bid it goodbye. Sometimes we can try, sometimes, just have to let it go.
