Jesus christ. If So Boerd wants to take Crayven Slaves he can take them by the thousands. I think a lot of people, who I shan't name, are too protective of their creations. If you come into an environment such as a NRP, of course they are going to be messed with and indeed I feel that if there is no good reason against it, then why not have some Lorenvolk slaves? It is more than possible that during a raid one would be wounded and captured or that young children would be kidnapped. I'll specify that going around a rhetoric that your people would never lose to a tiny raid because they are super warriors is annoying at best.

I'll just say to So Boerd that the Crayvens have a tendency to rebel against particularly oppressive regimes, a lot. Considering that the Crayvens are adaptable and breed fast, you could expect some Crayvens, especially newborns, to just say 'Well, this is life now!' and try to make the most of it, integrate themselves to your community and try to rise in ranks. However if you keep them down because of their race or even if you invite them to join your society but put in place age requirements that are unmeetable by a people living at most 40 to 50 years, you can expect mass rebellion once every decade or so.