How do I link it? And if I spawn the collision model won't the same thing happen?
the collision entity returned is like any other entity just call LinkTo(<parent>); on the collsion and it will be linked to it (have same origin and angles (with a offset of the distance away from parent))
EDIT: also you may need to precache and include the collsion model as 3arc maps dont precache or include some of them (if it doesnt work try precaching it if it still doesnt work add the include to your mod.csv still doesnt work after idk srry)