I don't know if this is a bug for my game somehow, or I'm just an impatient prick, but my companions just disappeared without a trace after I gave them fiefs.
I gave Lezalit Etrosq Castle, and Bahesthur Reveran village, and now they are nowhere to be found. Notes say that whereabouts unknown, faction notes say I have no vassals, and my ministers act like they never heard of them. (When I click I would like to send a message to a lord, or I want information about a lord, and select my faction, My character just says, Uuuh, never mind.)
EDIT: I don't know if this helps, but I finished the tutorial quest, and I had my kingdom destroyed once, but I re-established it.
I will try starting a new game, and be more careful, but I'm a bit bummed.