b2b organisation community

How to setup Organisation for a B2B workflow

I'm trying to model and run in portal a process where two organisations send messages between themselves.

In Bonitasoft you can only have one 'Active' organisation published. So how would you setup two pools, one for Acme and another for NotAcme for example?

Another way this impacts the process is with Authentication, you have to specify a user who is a member of 'the organisation', what happens if you need two?