As a test, I exported a Blender file that has 3 separate cubes (red, green, and blue). The goal is to have only 1 of these meshes load from the set (only the red cube, or only the blue cube, etc.). Which one loads should be random.
However, when using my imported meshes from Blender, I cannot replicate this effect. All three cubes load no matter what changes I make. Am I making a mistake with the hierarchy in Blender, or is this some type of coding mistake?