I know you're joking, but it's going to be something dumb like this that gets deniers to rethink their position. It may be some staple that disappears from shelves, or has to be replaced by an inferior substitute, or made with weird ingredients.
If lite beer had to be made with rice, or it got to $100 a case because of climate change fucking up the wheat crop, it would do more than every science paper in the world.
I still feel like it's idiotic to do work after you've been let go, I don't care how much your colleagues rely on you, the corporation decided you weren't worth keeping around. At least he's getting paid, but he could effectively be on a 9 month paid vacation doing literally anything else with his time.