There are c-suite execs out there with stutters. I will say that a lot of stuttering therapy is quite poor as they don't truly understand the issue or how to help. Most focus on fluency or control and that often does not work. I would advise to continue seeking therapy, but find something that makes sense to you that you believe in. I'd recommend a therapy focused around reducing avoidance, tension, and improving communication and expressiveness. None of that requires trying to control your stutter.