I've read enough of you info to provide the best and second best course of action.
Next time you log onto ALERTS you can look up yourself a few of the offenses this NCO is guilt of. The most basic is "using his grade and position to obtain pleasure, profit etc"
But since your Det is so small you don't want it getting back to you, after all you may likely still have to work with/for the guy on shift. Your in one of those small detachments that's so short everyone is on the access roster and your PS guy is probably dual hatted.
Your Commander who may be also a dual hatted PM/Commander may keep it internal and do the minimum. After all, if he was so great he would be commanding a line unit and not a Detachment.
As much as I hate to be on the receiving end of anonymous ICE complaints this is the best option for all parties.
Log on to the ICE website, not from work or the RTO computer. Maybe home or the library.
My first choice. Find your post and the organization DES/PMO. Simply state "I think its fucked up SSG X is using the NVGs for personal use"
The beauty of this is the Garrison Commander as well as the DES receive this and must respond. So the Garrison Commander will be aware. This means if your apathetic Commander or Provost Sergeant weren't going to do anything before they certainly will now.
The second best option is to leave out the guys name and say "someone". This allows everyone to lie and pretend it wasn't them or they were unaware. But it gets fixed.
If people are taking NVGs hunting god knows what else is wrong.
I'm against IG. Because they may simply refer it to the Commander. Again if he's a dual hatted guy, its his policies and apathy that enabled this. Without someone higher being aware he may simply do the minimum.
Also, many Detachments have the Garrison Commander in their rating chain.
Anyway I think this is best because anyone within the PMO you complain to won't likely keep your name out. Clearly this guy is senior to you or you'd have done something. If nothing major happens your stuck with him until one of you leaves. If your in an isolated detachment there is many options.
My money says a SSG, in which case you should use his full name. There is a bunch of MP SSGs getting looked at for QMP March 1st. Hopefully this guy is one of them.