Well today I had someone tell me they no longer work, but, they're stats are different than the vengeance batteries, and plasma cannon, it's just a russ turret plasma cannon being used.
I have the rules, but I'm looking for assistance in arguing against if I can use them or not.
Well, it would honestly depend on what you're trying to do. The models are Out of Print, so they are no longer made. They will not be receiving any additional rule updates beyond what you already own. So in a sense they are now invalid, due to the fact that their product line is gone.
So if you're trying to use them competitively, if your looking to play in a tournament I would ask the TO, generally I would expect to hear "no" regarding those turrets.
If you want to play a pickup game at a FLGS or at someone's place, I would just message your opponent if it is alright with them if you play them. Probably handicap yourself with using the old rules, until your gaming group can create its own errata for them.
The "rule of cool" applies here.
I would just say that each one counts as a fortification so you cannot spam them (unless that's the theme).
Sorry for npt being super helpful, it's just that most things that are A) FW or B) OOP, are usually not valid for competitive play here in the US because FW is kind of a bitch to get a lot of - or its OOP and no one besides the 1 player who has it can use them.