Seems legit, Norbyte is a name I recognize from Div modding days, doesn't surprise me that they've written some of the key scripts for BG3 stuff.
The new mod does at least credit Norbyte/fig/etc, essentially reposting their work with SEO and monetization is more than a little scummy, though. (I also don't know how to tell whether or not a mod is monetized, and if it's not I don't really care. But don't really have reason to disbelieve that particular claim. /shurg)