50 volts on hot to neutral but 120 volts with wall switch
Shouldn't that be Whiskey Tango Foxtrot? But I digress.

Anyway, I believe you are reading a static induced voltage that your very sensitive digital multi-meter is picking up.

If you were to test that with a solenoid voltage tester or maybe even a lamp tester I believe it will drop to zero. In other words, you meter does not put enough of a load on the test points to drag it down to zero.

Good luck!