If you stutter, let them wait. You have something important to say in a meeting say it. Because they want to hear it. If you do your job well, an i assume you do since you get the job offer in the first place, take it. For me the first days are the worst, new people to talk to and the stammer becomes worse. But when i work and focus on the work the pressure of speaking declines and my stammer practicly goes away. Its more a psychic problem then a physical problem. You don't stammer when you sing, almost every stammerer speaks fluently when he's alone. So don't focus on it too much, enjoy the good part of the job and the rest will come. I have full confidance you will do great and your stammer will decline!