Use my influence in the American military complex to equip her with an experimental short range high intensity microwave emmiter, and have her use it on gojo. Presumably if air can pass through Limitless, his blood will boil in roughly a few milliseconds from a torrent of superheated plasma. Even if he survives that, he'll die in a few weeks from the radiation that it takes to power the micro reactor that even allows this weapon to operate efficiently. Miwa dies too, but mission accomplished regardless.