2 mouths system not working

Hello i was playing around the idea of making a second mouth for my character and i woul like to switch from one to the other

Here is my hierachy

+Character

      Head

     |     Eyebrow

     |     Eyes

     |     |     +Mouth

     |     |      |    Mouth sad

     |     |      |    Mouth normal

     Body

So I wanted to use a trigger to switch from one to the other but when I get the two mouths the software doesn't seems to be able to see the second group of layers who have the same pheonems.

So my first group "Mouth sad" is working but my group "Mouth normal" is not.

So I guess the question is, is it possible to make it work ? Is there a hierachy trick or something that i could try?

Thanks