Hylden in SR1

[Kazame]

Does anyone know why we didnt see one hylden in the SR1 timeline? I mean, okay we know that in the BO2 timeline kain kills the SL and all, but in SR1, the timeline is still more original, and simple, or something. The pillars are destroyed, Kain is the last vamp, so he brings up his leitentants and they spawn their own clans... By this time I'd think hylden are roaming free as well, no? So what happens to them, do they get wiped out by the leutenants and their clans before the era of SR1? If this is so then raziel should have already known about the hylden every since SR1, but he doesnt. Any ideas?