Yes, my people could easily be enslaved by him...
If the Pelagian are allied with the pirates in my nation, they would get them VERY easily.
However, IN the core worlds, they would need to target single ships or little non-military, non-important fleets etc. which navigate trough galactic/planetary nebulas or other remote areas, since they are not guarded much...or he targets the "outer worlds", we have some colonies there (like minnig stations and some few settlements).