Voltage between neutral and ground in receptacle
The 56V is just a nonsense figure you are getting because you have a high impedance voltmeter, and it doesn't know what to do with what it's seeing.  This is the sign of a wire that is entirely disconnected from anything.  

It's not attached at the panel side (because of a defect), and it's not attached to hot via any loads, because you have removed them.  

If you plug in a load and turn it on, then the neutral should start behaving more predictably.  This will also correct for the error produced by your meter.