Can't Create Dynamic Material Instance for Destructible Mesh's 2nd material

I’m trying to create a destructible/breakable pot that fades away after a few seconds by setting the Opacity Parameter with a timeline after creating the dynamic materials, However, it’s not working. The second material (Element ID 1) is just getting set to the default grid material and I have no idea why. How can I fix this?

Thank you.

219343-screenshot-2017-11-06-132439.png

Still has the same issue unfortunately.

Hi. Try launch your project again, and check if the problem is still going on.

Hadn’t opened the project for months, opened it back up today and the issue is resolved?.. I didn’t do anything but it works now. So confused…