It seems like you’re making this harder than it needs to be. Or else, I don’t understand an aspect of your animation.
Here’s what I’d do:
Place all 4 objects in a 3D group. Space them however you like.
Add a camera.
Keyframe the X rotation of the 3D group so that all the objects spin at the same time.
Use the Point At behavior on each of the 4 objects so that they always point at the camera.
Am I missing something about this animation in which this method wouldn’t work?
Andy
https://www.timesavertutorials.com