No it’s not, dgu’s happen all the damn time. Hell there is a subreddit that tracks the ones that are found. There are countless videos of people being attacked, and pulling a firearm and the violence magically stops. That’s a DGU, even though no round was fired. So it doesn’t show up on lists like these, which have an agenda.
No I did not. And no there was not 1200 school shootings, those numbers are created by the GVA and used as a propaganda piece for anti-2a rhetoric.
Even NPR did a piece on it:
https://www.npr.org/sections/ed/2018/08/27/640323347/the-school-shootings-that-werent