Maybe could access top of winch if on a lift and you can get around spare tire to access the four bolts (11/12mm) to disconnect it and tire. More likely have to pull down entire cross beam with winch and spare attached. Be sure to support tire from dropping. Could then take out lock mechanism...
Very similar to lug nut lock. Luckily my dealer had a set of 10-12 assorted ones so I could lower the spare. Pix below show the other side b4 and after removal of the winch and lock side.