> Each time a node has an internal event, it hashes that event with k hash functions and increments its bloom filter.

Isn't this effectively the same as generating k random indices? In other words, would the bloom filter work equally well if we pick k random indices to update?

In regular bloom filters this won't work because we want identical elements to collide, but here that doesn't appear to be a concern. I can see how we might want identical nodes to collide (i.e. have the same node use the same indices over and over), but that is not what is going on.