I would just like to point out that there could be some unnecessary confusion regarding the name of the event.
DEF CON is already an established name for a conference with videos on Youtube. (google search:defcon events)
DEF CON is one of the world’s largest and most notable hacker conventions, held annually in Las Vegas, Nevada.
Using the same name would just create a lot of bounces from people that were searching for something else and consequently lower events discoverability in Google and Youtube search results.
Since DEFOLD could use any bit of help/boost it can get in recognition I would just recommend using full name instead.