Update: Post-processing to replace the option value for PlotRangePadding (which, strangely, is {{Scaled[0.02],Scaled[0.02]},{Scaled[0.02],Scaled[0.02]}} regardless of how the user sets this option)

lcp1 = ListContourPlot[XX, ColorFunction -> "TemperatureMap", 
    PlotLegends -> Placed[BarLegend[{0, 17, 34, 51, 67}, 
      LegendMargins -> {{0, 0}, {10, 5}}, 
      LegendLabel -> "% output", LegendMarkerSize -> 150, 
      LabelStyle -> {Italic, Bold, FontSize -> 15, FontFamily -> "Helvetica"}], 
    {{0.1, 0.5}, {0.1, 0.1}}], 
   Frame -> False,
   BoundaryStyle -> {Black, Thick}, Axes -> True];

lcp1 /. HoldPattern[PlotRangePadding -> _] :> (PlotRangePadding -> {{0, 0}, {.1, 0}})

Original answer:

Using

PlotRangePadding -> {{0, 0}, {0.1, 0}, Automatic}

eliminates the error message and gives

However, PlotRangePadding option values are simply ignored by ListContourPlot3D.

Update: A work-around: Post-processing to replace the option value for PlotRangePadding (which, strangely, is {{Scaled[0.02],Scaled[0.02]},{Scaled[0.02],Scaled[0.02]}} regardless of how the user sets this option)

lcp1 = ListContourPlot[XX, ColorFunction -> "TemperatureMap", 
    PlotLegends -> Placed[BarLegend[{0, 17, 34, 51, 67}, 
      LegendMargins -> {{0, 0}, {10, 5}}, 
      LegendLabel -> "% output", LegendMarkerSize -> 150, 
      LabelStyle -> {Italic, Bold, FontSize -> 15, FontFamily -> "Helvetica"}], 
    {{0.1, 0.5}, {0.1, 0.1}}], 
   Frame -> False,
   BoundaryStyle -> {Black, Thick}, Axes -> True];

lcp1 /. HoldPattern[PlotRangePadding -> _] :> (PlotRangePadding -> {{0, 0}, {.1, 0}})

Original answer:

Using

PlotRangePadding -> {{0, 0}, {0.1, 0}, Automatic}

eliminates the error message and gives

However, PlotRangePadding option values are simply ignored by ListContourPlot3D.

Use

PlotRangePadding -> {{0, 0}, {0.1, 0}, Automatic}

to get

Update: Post-processing to replace the option value for PlotRangePadding (which, strangely, is {{Scaled[0.02],Scaled[0.02]},{Scaled[0.02],Scaled[0.02]}} regardless of how the user sets this option)

lcp1 = ListContourPlot[XX, ColorFunction -> "TemperatureMap", 
    PlotLegends -> Placed[BarLegend[{0, 17, 34, 51, 67}, 
      LegendMargins -> {{0, 0}, {10, 5}}, 
      LegendLabel -> "% output", LegendMarkerSize -> 150, 
      LabelStyle -> {Italic, Bold, FontSize -> 15, FontFamily -> "Helvetica"}], 
    {{0.1, 0.5}, {0.1, 0.1}}], 
   Frame -> False,
   BoundaryStyle -> {Black, Thick}, Axes -> True];

lcp1 /. HoldPattern[PlotRangePadding -> _] :> (PlotRangePadding -> {{0, 0}, {.1, 0}})

Original answer:

Using

PlotRangePadding -> {{0, 0}, {0.1, 0}, Automatic}

eliminates the error message and gives

However, PlotRangePadding option values are simply ignored by ListContourPlot3D.