If Choji went over, he might see the supermarket packed with snacks, start stealing and stuffing himself, and completely ignore the surveillance.
If Ino went, they could seemingly eliminate one middleman, but she would very likely become lovestruck and obsessed with Shirozumi's looks.
Only Shikamaru was safe to send. They just needed to threaten him—if he dared slack off, he would be made to work a 996 schedule until he died of overwork afterward.
Shikamaru was not actually afraid of death, but he feared the process of dying, especially dying from overwork.
This mission, for example, was extremely dangerous.
Just as Kushina had said, Ada only gave Naruto special treatment and would not kill him.
Shikamaru would be risking his life by going to monitor her.
Yet Kushina had Shikamaru completely figured out. She knew he was not afraid of death; he was only afraid of being entangled in trouble and forced to work endlessly.
Death was not frightening. Death was a cool summer night, a carefree sleep.
Shikamaru decisively accepted the mission. Even if he died, he would not have to worry about people nagging him afterward, because he would have died carrying out a Hokage mission—a "legitimate death."
Thus, Shikamaru was very "brave." He walked straight into the supermarket, grabbed a bottle of drink, took out several coins, paid, and then sat directly on the steps outside the supermarket.
He monitored the inside just like that.
He even hoped Ada would come out and deal with him.
First, that would let his mission end early. Second, he could enjoy the carefree rest and treatment afforded to a war hero.
Unfortunately, Shikamaru had miscalculated.
Or rather, he knew he would not die like this. He was simply too eager for it.
After noticing Shikamaru, Ada did not care. With