I would think even if you hadn't heard ANY horror stories you would be scared.
It's scary to think your son might need help.
But know that the definition of COURAGE is to do the right thing in the face of insurmountable fear. That's from a movie I think. Or one of those plaques at Successories.
You are doing the right thing.
So, I have anxiety based OCD and it helps me to play worst case scenario.
I would think they would take him away in only 2 circumstances.
1. YOU have been abusive to your son and you refuse to stop abusing him or get any help.
2. Someone within the close family unit has been abusive to your son. You state out loud or even write a statement that says you plan to continue to keep your son in an active relationship with his abuser, regardless of the effect it is having on your son.
I would think those would be the ONLY reasons you would lose your son. It doesn't sound like either of those are your intentions. So, I wouldn't worry that they will take him away. Even if for some reason they decided he might benefit from some in patient time. But it doesn't sound like he is THAT dysfunctional. And even if they did want to hospitalize him that is ALWAYS temporary and wouldn't affect your custody as long as you are willing to do what is in his best interest.
So far, it sounds like you are very willing to do what's in his best interest, even when it put you out of your comfort zone. That is a good mom.
A bad mom is NOT a mom who can say "this issue is out of my realm of expertise and I prefer to have some help on this one". A good mom says that.
A bad mom is a mom who covers up her sons issues and doesn't seek help for her son because it's in the mom's best interest to hide what is really going on.
I think it's a whole basket of unknowns that has you so scared. And I think those feelings are completely justified.
The only way to combat those kind of fears is to know that what you don't know will help your son so you are going to find out what you don't know.
Please let us know how it goes and if you can think of specific things that would be supportive to you - please do them. A well-rested, well-fed mom will be much stronger to help your son with whatever it is that is going on.