@Count:
I still want that theory us forumers made about the Vinsmokes being the ones to end up wanting to destroy the cake come to reality. It's just so good. Especially when, despite teaming up with the Straw Hats at the wedding, they conveniently have no idea about the plan to feed Big Mom the cake and have yet to actively try to redeem themselves.
As much as I don't think it will happen, I do like this idea. If it were to happen as a result of Judge's leadership, I believe it would be from a similar motivation to Capone. Judge would see that Big Mom is getting weak in this state, possibly she starts lashing out at her own crew. If the Vinsmokes were to witness this, I could see Judge possibly wanting to destroy the cake and let Big Mom ruin her own empire for revenge. Sanji could fight his siblings and Dad, have a cool fight, then save the day with his cooking and show his family they're wrong.
But as much as I'd like to see it, I think that the Vinsmokes are already well on their path towards respecting Sanji, and that the fight would be retreading the same waters. I don't see Judge, their leader, being in the mindset to still want to continue screwing around in Tottoland on behalf of his dream to conquer North Blue. The only incentive he'd really have to attack the cake would be to keep Big Mom on her downward spiral. And he really has been shown to be more broken and defeated after the wedding than in a mood to get one last shot in on the Big Mom crew.
Maybe if Ichiji had been given more of an actual personality, I could believe the Vinsmoke boys deciding to attack the cake on their own, without Judge's direction. I feel like even now they'd still understand the opportunity they have and they'd seem more likely to want outright revenge than Judge. This honestly would set up a really cool fight, with Sanji needing to defend his food from his brothers. It's literally him dealing with his childhood grievances with his siblings in a fight where they still doubt his talents and look down on him. Sanji would beat his brothers, save the day with the cake, and the brothers would have a lot to think about after being defeated physically by Sanji and being proven wrong in front of all of Germa against the ugly duckling of their family.
Again, I still think we're more likely to have the Vinsmokes simply show up to help defend the cake in the final moments leading up to it being brought to Big Mom, but I like the idea of the Vinsmoke boys VS Sanji a lot more.