After searching the code, I found that the report works correctly when we see it in HTML format, but the pdf format does not work properly. Since we want the CVC component to use phantmjs to load the report, I tried to find a problem related to phantomjs and highcharts, but could not find anything.
Then I tried to look at the plotOption property and added the following plotOption to your code.
plotOptions: { series: { animation: false, stacking: 'percent', lineWidth: 1, fillColor: null, fillOpacity: 1, // this is default to 0.75 marker: { enabled: false } } },
Then it starts showing the result in PDF format. So the main culprit is fillOpacity. If you set it to 1, your problem will be solved.
Note. If you use fillOpacity other than 1, then this does not show the result.

You can also specify color, fill, and opacity, as shown below.
series: [{ name: 'that', data: [502, 635, 809, 947, 1402, 3634, 5268], fillColor:'red', // use this color light as compared to color fillOpacity: 1, color: 'white' // use this color dark as compared to fillcolor }, ... ... ... ,{ name: 'this too', data: [10, 30, 50, 105, 303, 801, 1020], fillColor:'#00ff00', fillOpacity: 1, color: 'orange' }]
You can download the code here.