The only way that slice() takes 5 arguments is if the last argument is a string indicating the interpolation method.
There are four-argument versions of slice() in which V is the first argument, but those only have one z.
There are seven-argument versions of slice() in which x, y, z, and v are the first four arguments, but the last three arguments must be xi, yi, zi. You seem to have left out the xi and yi.