You can't bullshit a man like that, and 4 guys with delta-ware wires III will kill us dead in a second. Spirits have to materialize and spells take time to cast. A deltaware ninja will win on the surprise test and ventilate us in a heartbeat.
Besides, a guy like Shotozumi is subtle. You don't become the head of the largest Yakuza ring by being ham-fisted.