That can be easilly brushed off. Might even be a red herring to make us believe it couldn't possibly be Vegapunk. There didn't seem to be much reason to even mention Vegapunk at that time, really.
And by brushing off, I meant there are ways in which Vegapunk might have made it seem like he's at his facility, while he was in fact somewhere else. Could have made a robot duplicate, or a clone, or both. He can make convincing robot versions of other people. Why not himself.
And as for silhouettes being different, it might just be Vegapunk with a different goddamn shirt on.
He maybe went there in his own mecha to confront Kaido, feeling guilt over his research being used like that, got promptly trashed by Kaido and thrown in a cell. It's a joke example, but you get the gist.
One possible way out for Luffy and Kid is Vegapunk agreeing to help Kaido, only to help Luffy and Kid escape.
True, putting it this way that guy can be anyone, especially since one the samurai silhouettes mentioned by Kinemon and Oden silhouette as well wear a straw hat. This guy might be one of them without the hat. I’m telling it from a plot and foreshadowing perception. Nothing hints toward Vegapunk if not for a similiarity in silhouettes (and silhouettes can be really decieving, especially in One Piece. If you think about the original Kaidou silhouette you can get my point). I don’t see the involvement of Vegapunk in this prison scenario, especially I don’t expect Vegapunk to have that personality. As I said in One Piece you can elaborate every kind of theories but Oda always builds a road to follow that’s costellated with foreshadows. In my opinion Vegapunk is dealing with the gigantified children at the moment (brought to him by Smoker, Fujitora is a friend of him, shares the same way of thinking and the two probably meet a lot. Also Fujitora mentioned Vegapunk regarding the Sichibukai situation, a theme that is the main core of Issho himself. I don’t see a red herring but the right character construction there).
That said, we have to wait for the reveal, hopefully in two weeks. If Oda wants to pull a huge twist here i keep telling that fishbone guy = Oden is the more fitting and more intriguing plot twist, story wise for this arc. But I suppose it’s more one of the two missing samurai.
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I like your theory even though 20 years is a long time. I decided to check momonosuke eyes and compare them to this mystery prisoner because if he is oden then only his son can have his eyes and they look like a match, both look like an upside down D, his pupils are more like Rogers.
Yeah, the eyes are the ones that got me the idea, actually. I didn’t mentioned them because, for example, even Sabo and Luffy share the same eyes but they are not blood related. Regarding the 20 years thing: in One Piece we have giants that live more than 300 years, an Admiral that didn’t eat for 2 straight years, a huge woman that can have 90 children and another one that was pregnant for 20 months (and the list can go on and on). A strong guy that can resist in a cell eating a not exactly healthy fish for 20 years doesn’t seem such a stretch, especially if that man is revealed to be one of the strongest samurai of Wano and a crucial member of Roger’s crew. Not to mention this guy is able to kill a man spitting a fish bone right into his neck from a distance, through a cage and with just his mouth .