I'm doing a similar setup, and tried your setup first. Then I had a look at the Scarecrow in the Farm scene and saw they have setup doing essentially that. However, they use an ObjectFollower Prefab which let's the snap zone (SZ) of the hat follow the position and rotation of the Head interactable. I copied this setup and it seems to work.
Also, look into if you need to add appropriate CollisionIgnore links between the interactables so they don't collide when not wanted. Scarecrow has that setup aswell.
Only drawback of the ObjectFollower right now that I experience is that there is a slight lag betwenn the position so it seems the Target objects are elastic to the Source objects when they follow. I posted a thread about that here, not sure on how to remedy as of now.