I think that after the final fall of the Republic, even more Nova Cats will move from there to the Protectorate.
How?
A, they are unlikely to learn of the Clan Protectorate
B, if they are on Drac worlds they are likely part of a pogrom
C, if they are on Cappie worlds they are likely in a gulag for being 'foreign invaders' or whatever MadCap's sidebar in SF was
D, if the Wolves took the world besides A you also have a lack of freedom of movement
E, if the Falcons took the world, you have A, lack of freedom of movement, lack of JS visiting, and possibly specifically targeted if in a enclave
F, behind the Fortress the Republic took steps to stomp out all the little factions w/ a 'join or die' as the least level of action (Bannson's nuts were just killed)
F2, the enclave militias- Wolf, HH, NC, GB, and maybe Fox- were all involved in absorbing territory contributing to destabilization
G, you are talking about identification after 10+ years of emergency programs & attendant indoctrination . . . heck, a whole generation of warriors would have grown up behind the Fortress wall