The first thing I would do is dispute the charge. I would do that before calling Lyft, because Capitol One kicks ass and takes names on my behalf every time I've needed them. As this happened after Coachella, you need to do this ASAP, as there's a limited time to dispute a charge.

If you don't get justice out of this, I would call the news media, hit up twitter, make as big a stink out of it as you can. You have to raise the cost of inaction on Lyft's side so that it's cheaper to just settle with you. The only way to do that is to make them hurt in the public sphere. After that, I would think about taking them to small claims court in the jurisdiction in which the crime occurred. In small claims court you can represent yourself and at least where I live there is an office that's there to help you. It is unlikely that Lyft would even show up to contest the case, as their lawyers are more expensive than your charge. Unfortunately, that works both ways and it's not worth you lawyering up either.

It should be abundantly clear from the GPS logs where this driver went during the time in question. Were they circling or aimlessly driving around to run up a fare? Or was this a point A to B drive that ended up at a residence, bar, or some other place that a human would go (ideally you could find their billing address).

I'm a driver and a pax, and my pax side says this stinks to high hell. My driver side says this could be a case of someone regretting a high charge. Please keep us updated on your story.

/u/lyft : Is it possible to cancel a ride in progress? If not, get ready for a sea of fraudulent charges because this is easy money if you are going to go all thug life on people with that TOS.