Real people organizing is very tough. I would find some folks who you could give you a firm “yes”, even if it’s supporting you while you try to stand something up. You can try draws, like “Free Pizza” if it wasn’t clear the food was free (best draw I know in America is free food). You can try signage around the campus physically, since a lot of younger folks ignore social media / FB. Tabling in person can work really well too. You need permission, a pop up table, signage, & a positive attitude.
Don’t beat yourself up over it. Organizing irl people is one of the harder things to do in this present moment.