Animate isn't exporting base layer

Hi, 

I've been trying to figure out why the first shot keeps exporting a grey background instead of the black it's supposed to be. I've attached both the export, what it's meant to be, as well as the file itself (only the first shot of it)

Project:

https://drive.google.com/file/d/1zfSaF3ocWAuEutlJGVMWscRcUIl2cZHk/view?usp=sharing