The quote from the Director of Event Services was quoted from Defensive Carry last June. In subsequent threads, one of the forum members called the director and posted this on 15 July:
"I just got off the phone with the Director of Event Services for the Nashville Music City Center.
It seems there's been a change of heart and legal carry will now be allowed at the 2015 NRA National Meeting.
Seems there was some push back from legal carriers like you and I. I wonder how much credit, if any, I'm entitled to.
Bill did say to make sure to check your "portability", I'm assuming he meant reciprocity."
I have seen nothing definitive on the NRA meeting website, or any other site for that matter. So it appears between 2 June and 15 July the director reconsidered his original email response, but again, nothing in writing that appears definitive.