We would see a hidden place to teach our children harmony. If they understand, perhaps we would return.
Make your peace with the galaxy. The rachni are a dead race.
And Gideon kills the queen.
If the queen is more certain in its abilities to reign her children, maybe Gideon wouldn’t have pressed the button to extinguish the last rachni queen.
From Gideon’s perspective, if is not good enough. This cannot happen again. The Rachni War of the history books can’t happen again.
So, he presses the switch, watches as the queen stares at him balefully and then struggles and screeches against the acid.
And when the acid dissipates, it is dead and slumped over.
That is when he finally let himself feel a single ounce of sadness in running a species into extinction.