From TalkOP:
黑玛利亚的部下们一脸“即便山治被殴打至此也不会出卖伙伴吧”的反应。
Black Maria's subordinates had a reaction of "Even if Sanji was beaten up to this point, he would not betray his partner, right?".
The call for help was a fluke So Robin would know where he was and could sneak attack them.
Robin can create eyes and spy, like she did in Thriller Bark and heard about the "nothing happenned".
She can easily do that and get the sneak attack on BM.
Easy bait, easy life.
黑玛利亚的部下们一脸“即便山治被殴打至此也不会出卖伙伴吧”的反应。
Black Maria's subordinates had a reaction of "Even if Sanji was beaten up to this point, he would not betray his partner, right?".
The call for help was a fluke So Robin would know where he was and could sneak attack them.
Robin can create eyes and spy, like she did in Thriller Bark and heard about the "nothing happenned".
She can easily do that and get the sneak attack on BM.
Easy bait, easy life.