Just had a quick scan through the code, and "set-camera-host" should be doing what is required.
I'm going to build a mini-mission now to see if it's working at all.
Edit:
Right, it does in fact do exactly what it says on the tin. It sets the camera to the origin of the stated sub-object, with the same orientation as the sub-object.
But... That's not actually what anybody would want, because the origin is almost always inside said sub-object.
So, it needs more data - it needs an offset in sub-object coordinates (X,Y,Z), so you can (for example) put the camera next to a turret and not have it always be physically inside.