Impedance
I'm not expert in this matter but few years ago I tested my helmet (Gentex SPH 4) on a Lama. The mic was not working. I swapped the 2 pins mic with the one from the headset and seemed to work properly.
Again, I'm not sure, I think the headset was a Clark. The mic were different only in the shape (and in the impedance of course).
I don't remember wether Peltor headset has a detachable mic or not, but if you have a 2 pins detachable mic, I would just try and if it works, test it properly or talk to a certified avionic engineer, just to be safe and legal.
Ciao ciao.