There is nothing wrong with murdering a million lives while iteratively developing – it's how we grow and study bacteria after all. Any person that fixed their gut by sticking to a diet also did exactly that.

So if we are concerned with the AGI suffering, then we don't need to determine consciousness at all. We just need to prove that they don't have suffering capabilities. Which is a way easier question.

It's easy to say it's easy, much more difficult to prove what can be idealized as suffering.

My daughter said she 'suffered' when I didn't get her ice cream (I know, I'm a monster). She didn't really suffer, but her behavior was as if she was.

So yes/no suffering is only part of the equation. Building systems that act/react like their suffering could be even more dangerous.