Not sure if others can test and confirm/deny this, but I have a feature service in AGOL with many domain driven fields. I've noticed that if I add a new item in the domain list in agol, the new coded value in the list is available to me from the attribute table drop-down in Pro, but it's not listed in the domain table.
Brooks_SummitGeo_0-1632215262004.png
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Still not fixed. Hope this is solved soon.