The structure of this feels off, the punchline already happened in panel two and the text in panel three isn't adding anything. A panel 3 without text would be funnier imo because it would let the joke soak, I also think moving the punchline to panel 3 would have worked better.
I think the punchline is him opening the vat so it can kill humanz and solve the climate crisis, without the third one it could just be him inventing random stuff/wasting money (I only got the joke on panel 3)