State Capitol building reciprocity?

[Armybrat]

Last week I took a North Dakota friend to see the State Capitol building. In accordance with the state procedure I got to bypass the security line with my Texas CHL (yes, I was carrying).
However, the troopers told my friend his North Dakota CHL wasn't good to do the same (he was not carrying). So he had to go through the metal detector and was "wanded" for good measure.

Are there some caveats to our reciprocity rules? I would think my out of state friend would've been afforded the same courtesy as I was.

[RoyGBiv]

State Capitol LE scans your license and compares it to the active CHL database to confirm it's a valid active license. Seems unlikely that SD enables Texas to make an instant check like that.