A22a+A22b Addendum
My mistake, I thought the Necromancy Arcane School just gave Channel (Negative) Energy.

So indeed when you select Command Undead as bonus feat from your Necromancy Arcane School the feat itself doesn't add anything (everything it adds is already gained by the first Command Undead feat from Undead Lord), but the class feature tied to it gives you more channels for that feat (or the feat from Undead Lord, doesn't matter really).

Or easier said: Yes, you are right.