I looked. The points are all baloney. And if the law REQUIRES you to allow firearms in vehicles, then you're off the legal hook for all of them.
"The point is, there are issues in this tension between a private landowner and the owner of a weapon desiring to leave it in his car. Frankly, as a business owner, I'd feel safer if he carried it into the building and checked it at the door."
Why???
"Wouldn't you?"
No.
"But then, how would you feel handing a loaded weapon to a guy you just fired?"
If the termination was fairly done and handled humanely, why would there be a problem. And if the terminee is deranged, your "no weapons on company grounds" will simply be ignored. This is the standard anti-gun BS. If the guy is planning to kill you, why is he going to follow any such rule???