There is one legitimate reason to have attended the meeting of fediverse admins with Facebook/Meta and that’s if your goal was to leak the contents.
(We’re waiting.)
Personally, I don’t see how I can trust any fediverse admin either stupid enough or malleable enough to sign an NDA with Facebook/Meta.
No one made you sign an NDA with a surveillance capitalist that this space stands in diametric opposition to. You did that to yourselves. Don’t be surprised if there are consequences.