Immunity to psychology (Itp) is part of the frenzy ability.
However, frenzy was changed long ago from wavering to 50% leadership and this negates half of the effect of immunity to psychology aka the terrorprevention.
Because terror only triggers at a certain (low leadership) point but frenzy already terminates far earlier this weakens the ability.
So I´d suggest cutting immunity to psychology from frenzy and adding +8 leadership instead.
This would still negate the penalty from "fear" while also making the ability more useful for the undead, who are not suceptable to fear/ terror already.
lowering the leadership requirement in such a way hat it includes the terror-trigger-point.