[Sig & ATPIAL question]

So you can put it on the MP5 but not the MPX, which is inaccurate. While the mpx gen 2 has the keymod hand guard, you can still mount rails to mount items and mount a peq-15 (atpial). I know because I own a gen 2 mpx which is what is modeled in the game. Wow, I was very impressed with how accurate they were initially. Wonder if they could throw that in a patch. 

[Sig & ATPIAL question]

I have a dumb question, or maybe I am just being obtuse. So I have the Sig MPX and I also have the Atpial laser to use with NV, but I can't seem to mount it on the MPX? Anyone else have this issue? There is a guide that says you can use it on sub machine guns which the MPX is? I can mount it on my ACR. Thanks for any help.