They can get fucked. How utterly unprofessional. I’d never want to work with people like that. If they mocked you they probably mock and bully others. I see two potential options: 1. You don’t get the job and don’t have to work with piles of shit for humans 2. You do get the job and can rub it in their face that people who stutter can do a good job, and I’d argue and even better job, than they can. Either way, that must have hurt. I’m really sorry that happened. People are asshole and people are especially assholes to anyone who falls outside the norm. Stuttering sucks sometimes. I wish you the best with future interviews and I hope a piano falls on those assholes.