Aren't there phase 3 trials already? Meaning that we are in fact already giving people experimental vaccines. Maybe if you had done it months ago it would have sped things up.
If you have well-informed volunteers like this willing to break with conventional rules, you can do a challenge trial where you deliberately expose them to live virus. That can work very fast indeed.
This question comes up a lot. Someone should really write a blog post about how big sample size you need, and the dangers of using a biased sample (fit men), and spam it to death here.