Answer

First, there is still a dispute about whether there is causality there at all. It depends on the interpretations. But even according to the common interpretation, which claims that there is no causality, that is on the local level. There is still causality in the sense that the quantum nature of the world causes things to happen in this way. In an empty world with no laws at all, particles would not emerge from the vacuum, nor would other quantum phenomena occur. The nature of the world is the causal factor behind quantum events.