Unfortunately it happens. If a capacitor is bad, it's like a 50/50 shot of survival on the electric motor or compressor. I would have checked the resistance of the windings, he may or may not have done that.
Only other thing I can say if the condenser coil is dirty it will cause high amp draw on the compressor.
You can check that by using a thermometer when the unit is running. Take the outside air temperature and then take the air temperature coming out of the top, if there's a 30 degree temperature difference you need to clean the condenser coil.