If I understand correctly, you'd like the labels above the columns formatted with a %.
You're not actually using stacking columns, but that is where the orange labels are coming from (stackLabels). So, remove those and then use the default placement for the column labels.

column: {

  dataLabels: {
    format: '{point.y:.1f}%',
    enabled: true,
    color: 'Black'

  colorByPoint: true,
  borderWidth: 0

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