Multiplayer BOTS with commander AI and Squad AI

I have been doing a to of research in my deep dive in to AI

I can easily do individual BOT AI but I would like to implement and three-layered hierarchy like killzone /3 and the older battlefield games.
With a Commander AI ,sending objectives to AI squads and those squad AI’s .
EG: The commander monitors the state of the game mode, assigns bots to squads, and issues objectives. The squad layer contains the AI for each of the squads. The Squad AI is responsible for translating objectives into orders.

But Im a bit confused as to what to make these AI Layers. as they don’t really need to exist physically.
I Do have a few Ideas about making them BT services But not sure how that would work just yet.
Has anyone here done anything similar or could offer some good advice?