There's no need to advertise the fact that we have slaves. We don't ride them, and they don't have a mark on their cheek. In reality, they're just servants, and no one needs to know about them. And if no one tells anyone, then no one will ever find out. At worst, we can come to an agreement and resolve the issue. And if it reaches the "highest levels," I think it goes without saying that Alex and I will personally handle the problem, without involving anyone else. You can even play dumb and say that they were just servants in your eyes, if necessary. There are many options.
As for the fact that we're not registering as an organization right away, I agree. I think that Alex, Heroist, and I (he'll do it through roleplaying anyway) can announce that we're one team. I think that's the best approach, and I wanted to mention it when I went through the process myself. The others don't really need to go into detail – as they said, they're just "with us" or "working for us."