How quickly does the average Free Code Camp graduate get accepted into a job?
I am unaware of any data on this. FCC does not really have graduates. It is not a school. It has certifications that users can earn and a ton of challenges and articles where users can learn how to program. Many users work through the challenges but may never complete the certifications. Instead, they may just create their own apps and portfolios and use those to get jobs.
It all depends on how much work you put in as a self-taught dev. FCC is just one source of learning how to program and people should remember that. Build your own projects and solve your own problems that can be solved with computer programming. Get ready to talk about your projects and other things you mentioned in your CV or portfolio in technical depth.
I personally believe having some core Computer Science knowledge is super important as well. It may just give you the edge in these interviews.