Hmmm... I think you do not populate the two series in the correct way because you always add Sektor and Branche together - I think you should add them independently, and in a way that the pies are still aligned. Study the attached demo which takes a few of your data with some random numbers - it is working as expected for me. Note that my values are "sales" rather than percentages, because with percentage it is not clear to what they refer: to the total of all sectors or to each individual sector only. It will be very difficult to align Sektor and Branche this way.
Also, I have the impression that this kind of application rather quickly brings the TAChart pie series to its limits: I wanted to add headers to the legend to group the legend by "Sektor", but found that headers can be added only per series, but not at any point in the value sequence. Or, I wanted to label the Branchen pies by numbers listed at the beginning at each legend item; here we have the limitation that series labels and legend labels must be the same...