Matua Tupuna + Necromantic Aegis?

Okay so, I found the shield Matua Tupuna Tarnished Spirit Shield.
It adds +2 to level of minions gems.
So I put my minion gems such as Summon Skeletons and Raise Zombie and Minion life in it. (It's a 3-linked.)
I saw this keystone passive skill a while ago called Necromantic Aegis that transfers all the shield's stats to your minions instead of you.
I'm wondering, does the +2 to level of minion gems go away... ? Or does it still apply to them?
I've been hesitating whether or not to put my skill point in it because I noticed when I put my gem in the shield as opposed to another item, the zombies' HP is greatly increased because it is 2 levels higher. I don't want that to go away if I put a skill point in it.

Since it effects the gems inside of it not you or your stats I think they should work fine but I know that any gems you put in your shield are still usable since my witch uses Necromantic Aegis and has gems in her shield.