Sorry to be the one to burst you bubble, but that stuff is not included in DCJS-mandated training because it has squat to do with what you were being trained to do. To be blunt about it, private security does not get any chance to violate the rights of anyone - the best you can ever hope to do is commit a felony crime with them as the victim.
I agree that it would be nice if private security knew what the basic laws were regarding firearm possession and self defense and a whole lot of other things. But for the most part you job, per the contract between the company that hired you and their client, is to observe and report. You can try to persuade someone to obey whatever rules the client has made, but unless you are certified both Armed and Arrest you cannot enforce them on your own. And even then you are not protected by even qualified immunity.
In my extremely un-humble opinion private security folks need to become adjusted to and accept the fact that they are not there to enforce the laws and have extremely limited ability to enforce the client's rules. The job is tough, and doing it well within the limitations imposed by DCJS, your company and the client as well as the law makes it even tougher. Maybe it would help if security folks remembered that if the client wanted someone to enforce the law they would have tried to hire their own police force. Oh, wait! That's not allowed*, is it? (We'll save the debate over off-duty cops acting as cops for later.)
In spite of everything above, I respect private security folks for what they do - when they stay wthin the rules and boundaries of their position. It's the cop wannabes that screw it up for the rest of you guys.
stay safe.
*I'm not going to get into Special Conservator of the Peace as so few private property owners bother to go that route and because the folks who get certified for that status do in fact go through the same training as the real cops.