Yep! Rasterization really messing things up! I didn’t know that you had a 3D replicator on the text. In the project you uploaded there was no replicator. Hey, if you still want that shadow, just duplicate the text layer, angle it 90 degrees, color it black, set the opacity to 50, and place it on the floor & enjoy animating! There ya go!
Flatten just screws the whole 3D up. Well, you have fun with the project!
~AJ