Unable to apply Materials to the chunks of a Destructible Mesh

When applying a second material to a Destructible Mesh it does not texture the chunks of the fractured mesh. The chunks remain the same as base color of the Destructible Mesh.

This is issue was reported and tested in 4.19.2 (CL-4033788). This issue was reproduced in 4.20.1 (CL-4233996) and Main 4.21 (CL-4234136)

1. Open the UE4 Editor
2. Create a destructible mesh based on Shape_Cube
3. Open the Destructible Mesh
4. Add an array element to Destructible Settings > Skeletal Mesh > Materials
5. Set array '1' to a different material than array '0'
6. Fracture the Mesh

Results: The array 1 material does not show up on the mesh. Both the inside and outside of the chunks use the material from array 0 only.

Expected: The inside of the chunks to use a separate material from the exterior.