I actually have a lot of content that was cut to keep the book to 64 pages. Mostly monsters, but I wanted to do some maps too. I don't remember if the Wealth domain was on that list as the cut was made over a year ago. However, I do remember my thought process was to list domains that made sense for Tiamat, whether or not they had "official" support.
If you want a wealth domain, here are some I found with a quick search:
Wealth Domain (GM Binder) - google drive direct link to PDF
Wealth Domain - findle wiki page
Domain of Wealth - World Anvill webpage