If Mr. Manifesto altered the magazine release lock to accommodate detachable magazines as this article hints, that would explain things.
Buffalo Shooter Saw New York's Gun Laws As His Advantage (msn.com)
"In the manifesto, Gendron allegedly wrote about how he planned to "kill as many Blacks as possible" in the attack and decided to carry it out in New York due to its strict open carry gun laws, which would make it harder for someone to stop him, the Buffalo News reported."
Did everyone get that? If not, got back and read it again.
You'll sit in a hotel conference room with lots of other people. Some people will talk to everyone else, maybe on a stage, maybe with a microphone, maybe even with accompanying visual displays. If you're lucky, there will be food/drink provided.
You'll likely hear RKBA-related info and news that you probably won't hear anywhere else. You may get solicited to participate in future activism, or to join or contribute to an organization or a campaign. You can choose to do so, or not do so. Maybe you'll even get an inkling that despite all the challenges there is hope for advancing the RKBA in NJ, that there is a large community of firearms enthusiasts and that you don't have to be a "closet-gun-owner", and that you have the ability to make a difference by contributing your efforts.
Eventually the event will end and you go home.