It's my belief that it's rare for evolution to screw up.

That's not how it works, I'm pretty sure... Mutations will have random effects and the species evolves based on characteristics being selected for based on better survivability, reproductive effectiveness, etc.

I would do everything I could to find an alternative solution and talk them down from it.

I've read your other messages and it seems that you're thoroughly convinced that this wasn't the case here. I suggest that you get a bit more context about this whole situation, as it has been a long path of trying multiple treatments and approaches, without any success. So it's not even remotely close to what you suggest here. No Futurama suicide chambers here.