Is there any way this can be prevented in the future?
Unfortunately, I can’t think of any way to add prevention measures that wouldn’t also open the door for some insanely transphobic practices. I think this is one of those things where you have to really rely on good faith behavior from the local community/people signing up for the event
100%. If you have $5-10 bucks to throw to the Democrats you could instead toss it to someone who actually needs it, like the UNRWA, or a local gofundme