I saw an excellent comment on YouTube from an individual named zexxer on Tekking101s newest video that got my brain thinking about who the ally Vegapunk mentioned in 1071 could be.
I think it’s Scopper Gaban for 3 reasons.
1 — There’s a Japanese TV Show produced by TOEI called Space Sheriff Gavan, with main character Space Cop Gaban. Scopper Gaban is based off of this character. The crazy part is that apparently in this show, Gaban uses a power called “scooper” TO SAVE A FAMOUS PROFESSOR.
2 — This arc is clearly the Sabaody Archipelago parallel for the start of the final saga with all of the characters and story beats. Silvers Rayleigh was introduced in Sabaody as the first legend we had met, the first mate (#2) of the Roger Pirates. Scopper (#3) being introduced here clearly parallel the introduction and serve well narratively to drop some endgame lore.
3 — The Roger pirates probably went into hiding, which explains why this person would be out of the spotlight. Someone that was part of the only group of people to have ever witnessed the One Piece and learn the worlds true history would definitely hide under someone has smart and as knowledgeable about the world like Vegapunk.
Theory by rikidilies (https://www.reddit.com/user/rikidilies)