You need to generate a different seed for each group. Right now you are asking every path to be assessed at the same random seed level. If you create a series of seeds with the same number in the series as the number of paths, and then plug this into the 'seed' value you will get what your looking for.
[Random] generates pseudo random numbers, meaning for a given seed value you will always get the same random distribution.
From your screenshot you are using a seed of 12. If you want to have a different random distribution for each branch you would need a different seed for each branch.
From your earlier post, it looks like you're trying to randomly remove points so a combination of [Jitter] and [Random Reduce] may work for you.
Thanks for the post Taz, I think the random reduce with jitter is a great way to achieve a random number list which I will probably end up using but I want to figure it out with the random generator as well for the sake of learning. If you can take a look at my file that would be great.