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Uncompress to get the three lists:
{vsoundAll, decAll, pdivAll} = Uncompress[compressed];
Replicate the issue:
ListLinePlot[{vsoundAll, decAll, pdivAll},
Frame -> True, Joined -> True,
PlotRange -> {{0.01, .4}, {0, 2}},
PlotStyle -> {"DarkColor", "Spahire", Red},
Filling -> {1 -> Top, 3 -> Top, 2 -> {3}}]

Several ways to fix:
1. Combine the second and third lists as Join[decAll, Reverse@pdivAll] and use it as the fourth input list and add 4 -> Bottom to the Filling option setting:
ListLinePlot[{vsoundAll, decAll, pdivAll, Join[decAll, Reverse@pdivAll]},
Frame -> True, Joined -> True,
PlotRange -> {{0.01, .4}, {0, 2}},
PlotStyle -> {"DarkColor", "Spahire", Red, LineOpacity -> 0},
Filling -> {1 -> Top, 3 -> Top, 4 -> {Bottom, LightGreen}}]

2. Construct a FilledCurve or Polygon using decAll and Reverse @ pdivAll:
ListLinePlot[{vsoundAll, decAll, pdivAll},
Frame -> True, Joined -> True,
PlotRange -> {{0.01, .4}, {0, 2}},
PlotStyle -> {"DarkColor", "Spahire", Red},
Filling -> {1 -> Top, 3 -> Top, 2 -> {3}},
Epilog -> {LightOrange, FilledCurve[Line /@ {decAll, Reverse@pdivAll}]}]

Using
Epilog -> {LightOrange, Polygon[Join[decAll, Reverse@pdivAll]]}
gives the same picture.
3. An alternative approach is to create BSplineFunctions from decAll and pdivAll and plot them using ParametricPlot:
Show[ListLinePlot[{vsoundAll, decAll, pdivAll}, Frame -> True,
PlotRange -> {{0.01, .4}, {0, 2}},
PlotStyle -> {"DarkColor", "Spahire", Red},
Filling -> {1 -> Top, 3 -> Top, 3 -> {2}}],
ParametricPlot[v BSplineFunction[decAll][t] +
(1 - v) BSplineFunction[pdivAll][t],
{t, 0, 1}, {v, 0, 1}, AspectRatio -> 1/GoldenRatio,
PlotStyle -> Green, BoundaryStyle -> None]]

{vsoundAll, decAll, pdivAll}are probably irrelevant here, from a problem-solving-strategy point of view, such assumptions are sometimes the reason problems don't get solved. For instance, this works for me:ListLinePlot[Table[Log[x] + k, {k, 3}, {x, 10}], Frame -> True, PlotRange -> {{1, 10}, {0, 6}}, PlotStyle -> {"DarkColor", "Saphire", Red}, Filling -> {1 -> Top, 3 -> Top, 2 -> {3}}]– Michael E2 Feb 09 '21 at 21:27