I'm not at all saying employees don't deserve to get what they are due, but if you have to get lawyers involved, for any amount less than six figures you aren't really going to be going home with a lot of money. Let's say a Twitter employee was making $300k. Three month's severance at full pay would be $75,000. By the time you pay the lawyers you might have enough left for a modest new car. And that's assuming you get the full award, my experience with arbitration is you agree to meet somewhere in the middle, because a full-on lawsuit after a failed arbitration will cost you even more.
Rather than deal with all of that, just move on. Get a new job, don't look back.