Somethings are more important than the fact they have already narrowly escaped a clutch of mandragora! Besides, Sephiroth is already mostly over that.

"Do you remember roughly where you might have dropped it?"

He's certainly not looking like he'd be letting this go just like that, especially without even trying. It might well just be a case that it was dropped en-route, which would mean they don't have to go all the way back there.