Shanks was found by Roger and his crew as a baby at God Valley incident? Who knows
Maybe. The manga only says he "grew up" in West Blue, but doesn't imply he was actually born there (only supplemental data books assume it). I'm not really sure myself what the timeline is meant to be.
God Valley would put Shanks at ~1 when it happened. Roger implies its been years since he held a baby and Film Red basically confirms he found him at least at a very young age (doesn't have to be God Valley). But he also was with Roger until he was 15 (24 years ago), so I'm not sure how he grew up in WB unless it was after (ofc it could be he was much older when Roger met him).
Now, is he actually a CD? I personally don't know, but imo, he's a "nobody" at this point. No special lineage. No living wills. Nothing. But then that's pretty counterintuitive to his relevance/importance to a Fleet Admiral and Gorosei. He's very much about keeping the peace and maintaining balance, which is probably why they respect him.
However that basically goes against what Luffy will likely end up doing by the EoS. Really lots to think about.
Thanks for bumping this guys lol