That's your instincts are right, that's largely the case. Most SLPs ranking stuttering as their least confident condition. I also believe it's the most different to other speech issues. You need an expert in stuttering and even then it's hard to find one who actually understands it. Someone who knows how to work on secondaries and who actually understands what acceptance is and how to get there. But if you can find one it's worth it. Honestly, if you live in the US, the best thing I can recommend is to get involved with FRIENDS. Go to the annual convention if you can. That's a really great environment. It's the biggest recommendation I have.  https://friendswhostutter.org