Multicam and some micro problem sound

Good morning, 
If anyone could help me with a multicam project that would be great! 
I explain my problem with Premiere Pro. 

I want to edit a multicam video with 5 cameras.

So I have the 5 cameras (including 1 without audio, dressing plans). 
But I also have 2 additional audio tracks which are the lavalier microphones of the two people in the video. 
I also have the original sound from the camera to synchronize everything. 

The problem being that I have two characters and therefore two audio tracks but when I do my multicam sequence I set the synchronization to the audio but the two microphones are off the multicam. 

that is to say that the multicam does not automatically cut the correct audio track but that of the camera. 

is this normal? Is there a method to manage the different microphones in multicam? 

Or do we have to manually mute the person speaking on each microphone and mute the other at the same time? 
(second problem if you have a solution better than mine I am interested: 1 video does not have the same sound and therefore impossible to synchronize this one with the others with the audio because it does not have any. So I add it manually to the multicam edit because very little sequence was used, it's dressing shots but synchronized on the same shoot)

thank you for your answer if you can help me !