In theory, using the job centre is perfectly fine.
It's similar to 03/04 having your scouts show up players from obscure African or Caribbean nations when you were scouting England. Your scouts theoretically found them, so they were fair game.
As a rule of thumb, though, you wouldn't normally hire a staff member who doesn't speak the native language of your country.
As unlikely as foreigners might be, they applied for the job you advertised, so they're pretty much fair game as far as I'm concerned.
Ian would have the final say, though.