When I do this sort of thing, with few pieces like in the video I simply fracture a groundplane, animate a sphere through it. Remove the static pieces and convert the result to a bone animation to be used in Unreal as a skeletal mesh.
Shattered floor.
Collision sphere animated into floor.
Remove the unused pieces.
Bake down to parts Unreal can convert to a skeletal mesh.
Done! Shove it into game.
Note: Spend more than 10 minutes on it to get better results 