Why can I not render a displacement map animation?

I’ve followed a Gleb Alexandrov tutorial (2.77) up to this point, using Blender 2.82. However, I can’t seem to get Cycles to render the required displacement maps. Can anybody tell me how to get over this hump?

You should be able to download my .blend here!

Baked the canvas dynamics, switched the renderer to Eevee and it turned out fine. =/