As a software engineer, I could not care less about how a bug was found or by whom, as long as I can quickly verify it is correct, I always appreciate being able to improve my work. I don't see why it should be different for mathematicians (the ones I knew would think similarly, I would assume.)

> They didn't just generate something with a magic box.

It doesn't matter who found the error nor how it was found. An error is an error.