Looks like aside from the scale attacking your plant, it also has some bacterial rot ongoing. I would suggest you treat the scale infestation, remove all the rotten branches like that, repot to a new porous soil. Keep the plant in a shady side and hopefully it will recover.
You may also want to try and start some leaf cuttings as back-up. It is going into summer, and weather is warm, so it will not be too difficult to root new cuttings.
