Particle Instance of Multi Object Group Containing Particles

I have a model of a bush for an outdoor scene. The model is made up of several objects for the branches (some have particles and some don’t), and leaves are formed on the branches by a particle system with object instance. I am trying to find a way to instance the bush to use in a large outdoor scene. I’d rather not convert the leaves to a mesh as I’m trying to keep the poly count down so I can still work in the scene.

My research suggests that using the particle instance modifier might be the way to go, but I can’t seem to figure out the step by step in order to make all the objects and the leaves appear where they are supposed to.

This link is more or less what I’m trying to achieve, but can’t get the modifier to work properly with the leaves and the group. I feel like I’m just missing something fundamental.

If someone could shed some light on the steps to take to instance a group of objects that contains a particle system, I’d greatly appreciate it.