Suppose Bill was making 4680 cells in Nevada, knowing they were destined to be made into packs at Fremont. He sees the signed pack photo and goes "ahah, there it is, confirmed", not twigging that the makers of the 18650 non-structural plaid pack were equally proud of their work.
I think Fremont is making 4680 packs and maybe Nevada is making 4680 cells, but the photo is of a non structural 18650 pack. The other possibility is that Bill went to Kato Road where he had his hands on 4680 cells. Photos are nice, but it's the facts that matter.