Interesting point, and I can't help him.
Some time ago I sent an internal email to the site manager with a link to the new law here in Texas, let him know I am a CHL holder and I will be carrying on site and storing in my locked truck on company property (an otherwise "gun free" property).
I urged him to make the site population aware of this new law in case someone saw me moving my sidearm from holster to the lock-box or back to holster at the end of the day.
Not a peep.
I make a point to be discreet and I hope at least that site security is aware I'm legal...
More discreet is: Don't ask, don't tell.