I’m late to this question, as I can see in your edit that you already passed the first interview - Congratulations, well done ☺️ But to give an advice to others, on how to get through a job interview, I’d say that you come a long way with being honest about it. I’m 50 years old, so I’ve been to many job interviews, and I’ve always told them that I have a stutter. It takes a lot of pressure off ones shoulder, when you dont’t have to hide it (my stutter is severe, especially in situations where I feel insecure, like job interviews f.ex.).