Start deactivated for RBD not working? Little control?

I am trying to make an object burst out from inside another object with RBD. I fracture the external object with cell fracture, and then hit start deactivated so that in theory when the object burst from inside everything stays still except the pieces that the inside object collides with. This is not working. When the now activated pieces interact with each other it creates a domino effect and suddenly everything falls to the ground.

It should be so simple. Make a and b and c pieces dynamic as soon as x collides with them. that’s literally everything I need.

Also, constraints have not worked for me either as a way to keep them still until the object collides, becausethe external object is not uniform (the destroy walls tutorials don’t help me here, my pieces dont just stack and stay put). Imagine that I need more of a hollow shape like a vase or whatever getting hit by a bullet and only breaking the area wherer the bullet goes through, not the whole thing.