Can you post a picture please.

Here is the photo. It's really drooping. What if I cut it and try to root it? Do you think it might work?

That’s very odd. I’ve never seen a Fuchsia suddenly collapse like that. It’s a lot worse than simply drooping. There’s nothing on the larger plant which would make viable cuttings. All I can suggest is cutting back the dying stuff and hoping for the best. Spraying with water, btw, will have no effect on hydration. Did you apply the fertiliser at the recommended solution?

Yes, I did, but if I hadn’t wouldn’t the smaller one have died, too? A real conundrum. Thanks for your input.