I want to know the answer to the following question:
Which Swiss victory in 1499 amounted to de facto independence within the Holy Roman Empire?
All the background I'm provided with is that "By 1460, the confederates controlled most of the territory south and west of the Rhine to the Alps and the Jura mountains, particularly after victories against the Habsburgs (Battle of Sempach, Battle of Näfels), over Charles the Bold of Burgundy during the 1470s, and the success of the Swiss mercenaries.". Is that enough to answer the question?
Answer: no