Since Dietre won't be owned by Desi, its possible he met Maya at a halfway house, though he was only very recently sent to one, so if she's been owned for more than a few months, they would have missed being there at the same time.
Dietre would probably get along with Ladera, if she can handle being around someone as inwardly nervous and depressed as Dietre, since being an empath she might have to deal with his emotions?