The scripting commands for adding and removing weapons do not work on night vision goggles, though they do work for binoculars and other items in cfgWeapons.
In the reproduction, binoculars were used to verify since "NVGoggles" is a subclass of "Binocular" in cfgWeapons.
this addWeapon "NVGoggles"; this addWeapon "Binocular";
this is the command for adding the night vision-goggles:
this addItem "NVGoggles"; this assignitem "NVGoggles";
when removing them, as one might expect, you have to unassign them first and then remove the item. Hope this helps.