I assume this artificial world's tin box is different from real world's tin box, because in early chapter Kenji's group dug the box on found nothing of this remote control shit
Otherwise it's a plot hole
Sadakiyo death is very sus. He dead off-screen (or whatever it called) and the only mention is few panel saying a man died in car accident. Doesn't even confirmed, Kanna's gang just assume he's dead.
Is he pulling the string behind this?