User blog comment:Kaido King of the Beasts/Chapter 870: There and Back Again/@comment-3529684-20170630005707/@comment-2001:8003:1172:2900:B40C:1229:6329:686D-20170701190326

I agree with the third guy, it can't be even sure if Luffy and Sanji even knew if Reiju was in danger befire they attacked and their dialogue afterwards is about "going all out". Really Sanji as well as Luffy are actuallly attacking Zeus, still technically Big Mom by extension, but not her directly.

Also Sanji was prepared to shoot Big Mom when planning the wedding.