OK for all heres the fix its simple once I figured it out....
Only one catch tho it wont work with just any unit.
In the editor u add any unit that is sidearm capable i.e. the new resistance guys or can be any addon unit that can use a sidearm. Then in the description.ext u add any sidearm u like to the usual class weapon list
For example:
class KEGsw44m
{
count = 4;
};
then when u start up the game u will see the unit has his assigned pistol but u will also be able to choose any one u have added and dont forget to add the magazines in also under the class magazines field. SO basically the fix was you just need a sidearm capable unit and then add the weapon like u would any other.
If anyone would like a copy of my universal description.ext that covers most coop multi missions let me know and ill give it to ya then u can edit it how u see fit.